From 7b9cd09c2ef67006e824704d36019dd0606f0a32 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 17:35:37 +0900
Subject: [PATCH 01/19] chore: initial setting

---
 .gitattributes                                |   9 +
 .gitignore                                    | 182 +++++++++++++
 app/build.gradle                              |  35 +++
 .../test/java/com/programmers/AppTest.java    |  14 +
 gradle/wrapper/gradle-wrapper.properties      |   6 +
 gradlew                                       | 244 ++++++++++++++++++
 gradlew.bat                                   |  92 +++++++
 settings.gradle                               |  11 +
 8 files changed, 593 insertions(+)
 create mode 100644 .gitattributes
 create mode 100644 .gitignore
 create mode 100644 app/build.gradle
 create mode 100644 app/src/test/java/com/programmers/AppTest.java
 create mode 100644 gradle/wrapper/gradle-wrapper.properties
 create mode 100755 gradlew
 create mode 100644 gradlew.bat
 create mode 100644 settings.gradle

diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 000000000..097f9f98d
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1,9 @@
+#
+# https://help.github.com/articles/dealing-with-line-endings/
+#
+# Linux start script should use lf
+/gradlew        text eol=lf
+
+# These are Windows script files and should use crlf
+*.bat           text eol=crlf
+
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 000000000..75dbe68c3
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,182 @@
+# Ignore Gradle project-specific cache directory
+.gradle
+
+# Ignore Gradle build output directory
+build
+
+# Created by https://www.toptal.com/developers/gitignore/api/macos,java,intellij
+# Edit at https://www.toptal.com/developers/gitignore?templates=macos,java,intellij
+
+### Intellij ###
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio, WebStorm and Rider
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff
+.idea/**/workspace.xml
+.idea/**/tasks.xml
+.idea/**/usage.statistics.xml
+.idea/**/dictionaries
+.idea/**/shelf
+
+# AWS User-specific
+.idea/**/aws.xml
+
+# Generated files
+.idea/**/contentModel.xml
+
+# Sensitive or high-churn files
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+.idea/**/dbnavigator.xml
+
+# Gradle
+.idea/**/gradle.xml
+.idea/**/libraries
+
+# Gradle and Maven with auto-import
+# When using Gradle or Maven with auto-import, you should exclude module files,
+# since they will be recreated, and may cause churn.  Uncomment if using
+# auto-import.
+# .idea/artifacts
+# .idea/compiler.xml
+# .idea/jarRepositories.xml
+# .idea/modules.xml
+# .idea/*.iml
+# .idea/modules
+# *.iml
+# *.ipr
+
+# CMake
+cmake-build-*/
+
+# Mongo Explorer plugin
+.idea/**/mongoSettings.xml
+
+# File-based project format
+*.iws
+
+# IntelliJ
+out/
+
+# mpeltonen/sbt-idea plugin
+.idea_modules/
+
+# JIRA plugin
+atlassian-ide-plugin.xml
+
+# Cursive Clojure plugin
+.idea/replstate.xml
+
+# SonarLint plugin
+.idea/sonarlint/
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+com_crashlytics_export_strings.xml
+crashlytics.properties
+crashlytics-build.properties
+fabric.properties
+
+# Editor-based Rest Client
+.idea/httpRequests
+
+# Android studio 3.1+ serialized cache file
+.idea/caches/build_file_checksums.ser
+
+### Intellij Patch ###
+# Comment Reason: https://github.com/joeblau/gitignore.io/issues/186#issuecomment-215987721
+
+# *.iml
+# modules.xml
+# .idea/misc.xml
+# *.ipr
+
+# Sonarlint plugin
+# https://plugins.jetbrains.com/plugin/7973-sonarlint
+.idea/**/sonarlint/
+
+# SonarQube Plugin
+# https://plugins.jetbrains.com/plugin/7238-sonarqube-community-plugin
+.idea/**/sonarIssues.xml
+
+# Markdown Navigator plugin
+# https://plugins.jetbrains.com/plugin/7896-markdown-navigator-enhanced
+.idea/**/markdown-navigator.xml
+.idea/**/markdown-navigator-enh.xml
+.idea/**/markdown-navigator/
+
+# Cache file creation bug
+# See https://youtrack.jetbrains.com/issue/JBR-2257
+.idea/$CACHE_FILE$
+
+# CodeStream plugin
+# https://plugins.jetbrains.com/plugin/12206-codestream
+.idea/codestream.xml
+
+# Azure Toolkit for IntelliJ plugin
+# https://plugins.jetbrains.com/plugin/8053-azure-toolkit-for-intellij
+.idea/**/azureSettings.xml
+
+### Java ###
+# Compiled class file
+*.class
+
+# Log file
+*.log
+
+# BlueJ files
+*.ctxt
+
+# Mobile Tools for Java (J2ME)
+.mtj.tmp/
+
+# Package Files #
+*.jar
+*.war
+*.nar
+*.ear
+*.zip
+*.tar.gz
+*.rar
+
+# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+hs_err_pid*
+replay_pid*
+
+### macOS ###
+# General
+.DS_Store
+.AppleDouble
+.LSOverride
+
+# Icon must end with two \r
+Icon
+
+
+# Thumbnails
+._*
+
+# Files that might appear in the root of a volume
+.DocumentRevisions-V100
+.fseventsd
+.Spotlight-V100
+.TemporaryItems
+.Trashes
+.VolumeIcon.icns
+.com.apple.timemachine.donotpresent
+
+# Directories potentially created on remote AFP share
+.AppleDB
+.AppleDesktop
+Network Trash Folder
+Temporary Items
+.apdisk
+
+### macOS Patch ###
+# iCloud generated files
+*.icloud
+
+# End of https://www.toptal.com/developers/gitignore/api/macos,java,intellij
\ No newline at end of file
diff --git a/app/build.gradle b/app/build.gradle
new file mode 100644
index 000000000..df7b83fc3
--- /dev/null
+++ b/app/build.gradle
@@ -0,0 +1,35 @@
+/*
+ * This file was generated by the Gradle 'init' task.
+ *
+ * This generated file contains a sample Java application project to get you started.
+ * For more details take a look at the 'Building Java & JVM projects' chapter in the Gradle
+ * User Manual available at https://docs.gradle.org/8.0.2/userguide/building_java_projects.html
+ */
+
+plugins {
+    // Apply the application plugin to add support for building a CLI application in Java.
+    id 'application'
+}
+
+repositories {
+    // Use Maven Central for resolving dependencies.
+    mavenCentral()
+}
+
+dependencies {
+    // Use JUnit Jupiter for testing.
+    testImplementation 'org.junit.jupiter:junit-jupiter:5.9.1'
+
+    // This dependency is used by the application.
+    implementation 'com.google.guava:guava:31.1-jre'
+}
+
+application {
+    // Define the main class for the application.
+    mainClass = 'com.programmers.App'
+}
+
+tasks.named('test') {
+    // Use JUnit Platform for unit tests.
+    useJUnitPlatform()
+}
diff --git a/app/src/test/java/com/programmers/AppTest.java b/app/src/test/java/com/programmers/AppTest.java
new file mode 100644
index 000000000..979944084
--- /dev/null
+++ b/app/src/test/java/com/programmers/AppTest.java
@@ -0,0 +1,14 @@
+/*
+ * This Java source file was generated by the Gradle 'init' task.
+ */
+package com.programmers;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+class AppTest {
+    @Test void appHasAGreeting() {
+        App classUnderTest = new App();
+        // assertNotNull(classUnderTest.getGreeting(), "app should have a greeting");
+    }
+}
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 000000000..bdc9a83b1
--- /dev/null
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,6 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.0.2-bin.zip
+networkTimeout=10000
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/gradlew b/gradlew
new file mode 100755
index 000000000..79a61d421
--- /dev/null
+++ b/gradlew
@@ -0,0 +1,244 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/HEAD/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+# This is normally unused
+# shellcheck disable=SC2034
+APP_BASE_NAME=${0##*/}
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC3045
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC3045
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+# Collect all arguments for the java command;
+#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+#     shell script including quotes and variable substitutions, so put them in
+#     double quotes to make sure that they get re-expanded; and
+#   * put everything else in single quotes, so that it's not re-expanded.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"
diff --git a/gradlew.bat b/gradlew.bat
new file mode 100644
index 000000000..93e3f59f1
--- /dev/null
+++ b/gradlew.bat
@@ -0,0 +1,92 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%"=="" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%"=="" set DIRNAME=.
+@rem This is normally unused
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if %ERRORLEVEL% equ 0 goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if %ERRORLEVEL% equ 0 goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/settings.gradle b/settings.gradle
new file mode 100644
index 000000000..97ca62449
--- /dev/null
+++ b/settings.gradle
@@ -0,0 +1,11 @@
+/*
+ * This file was generated by the Gradle 'init' task.
+ *
+ * The settings file is used to specify which projects to include in your build.
+ *
+ * Detailed information about configuring a multi-project build in Gradle can be found
+ * in the user manual at https://docs.gradle.org/8.0.2/userguide/multi_project_builds.html
+ */
+
+rootProject.name = 'java-calculator'
+include('app')

From 289bad691f102bc38131678cf094e7d44d220119 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 17:37:00 +0900
Subject: [PATCH 02/19] =?UTF-8?q?feat:=20=EA=B3=84=EC=82=B0=EA=B8=B0=20?=
 =?UTF-8?q?=EC=A0=84=EC=B2=B4=20=EB=8F=99=EC=9E=91=20=EA=B3=BC=EC=A0=95=20?=
 =?UTF-8?q?=EC=A0=95=EC=9D=98?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 app/src/main/java/com/programmers/App.java | 60 ++++++++++++++++++++++
 1 file changed, 60 insertions(+)
 create mode 100644 app/src/main/java/com/programmers/App.java

diff --git a/app/src/main/java/com/programmers/App.java b/app/src/main/java/com/programmers/App.java
new file mode 100644
index 000000000..ffb0437d2
--- /dev/null
+++ b/app/src/main/java/com/programmers/App.java
@@ -0,0 +1,60 @@
+/*
+ * This Java source file was generated by the Gradle 'init' task.
+ */
+package com.programmers;
+
+import com.programmers.calculator.Calculator;
+import com.programmers.io.IOConsole;
+import com.programmers.memory.HistoryMemory;
+
+import java.io.*;
+
+public class App {
+    // 계산기 옵션
+    private static final String SHOW_HISTORY_OPTION = "1";
+    private static final String CALCULATE_OPTION = "2";
+
+    private static final IOConsole ioConsole = new IOConsole(); // 입출력 콘솔
+    private static final Calculator calculator = new Calculator();  // 숫자 계산을 담당하는 부분
+    private static final HistoryMemory historyMemory = new HistoryMemory(); // 계산 결과 메모리
+
+    public static void main(String[] args) throws IOException {
+        while (true) {
+            ioConsole.printMenu();
+
+            String option = ioConsole.getOption();
+
+            switch (option) {
+                case SHOW_HISTORY_OPTION: {  // 1. 조회
+                    String history = historyMemory.getHistory();
+                    ioConsole.print(history);
+                    break;
+                }
+                case CALCULATE_OPTION: {  // 2. 계산
+                    String inputExpression = ioConsole.getInput();
+
+                    if (!ioConsole.validateInputExpression(inputExpression)) {
+                        break;
+                    }
+
+                    try {
+                        String convertedExpression = calculator.convert(inputExpression);
+
+                        double answer = calculator.calculate(convertedExpression);
+
+                        historyMemory.saveHistory(inputExpression, answer);
+
+                        ioConsole.printAnswer(answer);
+                    } catch (Exception e) {
+                        ioConsole.print(e.getMessage() + "\n");
+                    }
+                    break;
+                }
+                default: {  // 잘못된 입력을 처리
+                    ioConsole.handleWrongInput();
+                    return;
+                }
+            }
+        }
+    }
+}
\ No newline at end of file

From c65c229879c51acf7db3f0a65b79d796fcf40fe3 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 17:47:59 +0900
Subject: [PATCH 03/19] =?UTF-8?q?feat:=20=EB=A9=94=EB=89=B4=20=EC=B6=9C?=
 =?UTF-8?q?=EB=A0=A5=20=EA=B8=B0=EB=8A=A5?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../java/com/programmers/io/IOConsole.java    | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 app/src/main/java/com/programmers/io/IOConsole.java

diff --git a/app/src/main/java/com/programmers/io/IOConsole.java b/app/src/main/java/com/programmers/io/IOConsole.java
new file mode 100644
index 000000000..7f9329d03
--- /dev/null
+++ b/app/src/main/java/com/programmers/io/IOConsole.java
@@ -0,0 +1,19 @@
+package com.programmers.io;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+
+public class IOConsole {
+    // 사용자에게 보여주는 메뉴 메시지
+    private static final String HISTORY_OPTION_MESSAGE = "1. 조회";
+    private static final String CALCULATE_OPTION_MESSAGE = "2. 계산";
+    /**
+     * 계산기의 선택 메뉴를 출력하는 함수
+     */
+    public void printMenu() {
+        System.out.println(HISTORY_OPTION_MESSAGE);
+        System.out.println(CALCULATE_OPTION_MESSAGE);
+        System.out.println();
+    }
+}
\ No newline at end of file

From 146fb4e5c5bc1951d02bd4c9ae9599df84821dfd Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 17:50:31 +0900
Subject: [PATCH 04/19] =?UTF-8?q?feat:=20=EC=82=AC=EC=9A=A9=EC=9E=90?=
 =?UTF-8?q?=EC=9D=98=20=EC=9E=85=EB=A0=A5=EC=9D=84=20=EC=B2=98=EB=A6=AC?=
 =?UTF-8?q?=ED=95=98=EB=8A=94=20=EA=B8=B0=EB=8A=A5?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../main/java/com/programmers/io/IOConsole.java   | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/app/src/main/java/com/programmers/io/IOConsole.java b/app/src/main/java/com/programmers/io/IOConsole.java
index 7f9329d03..a2b29781e 100644
--- a/app/src/main/java/com/programmers/io/IOConsole.java
+++ b/app/src/main/java/com/programmers/io/IOConsole.java
@@ -8,6 +8,7 @@ public class IOConsole {
     // 사용자에게 보여주는 메뉴 메시지
     private static final String HISTORY_OPTION_MESSAGE = "1. 조회";
     private static final String CALCULATE_OPTION_MESSAGE = "2. 계산";
+    private static final String USER_CHOICE_MESSAGE = "선택 : ";
     /**
      * 계산기의 선택 메뉴를 출력하는 함수
      */
@@ -16,4 +17,18 @@ public void printMenu() {
         System.out.println(CALCULATE_OPTION_MESSAGE);
         System.out.println();
     }
+
+    /**
+     * 사용자의 선택을 받아 반환하는 함수
+     *
+     * @return
+     * @throws IOException
+     */
+    public String getOption() throws IOException {
+        System.out.print(USER_CHOICE_MESSAGE);
+        String expression = br.readLine();
+        System.out.println();
+
+        return expression;
+    }
 }
\ No newline at end of file

From 69923ac924827fdbd72d91d839c196d850d1d512 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 17:51:46 +0900
Subject: [PATCH 05/19] =?UTF-8?q?feat:=20=EC=82=AC=EC=9A=A9=EC=9E=90?=
 =?UTF-8?q?=EC=9D=98=20=EC=9E=85=EB=A0=A5=EC=9D=84=20=EB=B0=9B=EB=8A=94=20?=
 =?UTF-8?q?=EA=B8=B0=EB=8A=A5?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 app/src/main/java/com/programmers/io/IOConsole.java | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/app/src/main/java/com/programmers/io/IOConsole.java b/app/src/main/java/com/programmers/io/IOConsole.java
index a2b29781e..e51c2f37d 100644
--- a/app/src/main/java/com/programmers/io/IOConsole.java
+++ b/app/src/main/java/com/programmers/io/IOConsole.java
@@ -9,6 +9,8 @@ public class IOConsole {
     private static final String HISTORY_OPTION_MESSAGE = "1. 조회";
     private static final String CALCULATE_OPTION_MESSAGE = "2. 계산";
     private static final String USER_CHOICE_MESSAGE = "선택 : ";
+    private static final BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+
     /**
      * 계산기의 선택 메뉴를 출력하는 함수
      */
@@ -31,4 +33,14 @@ public String getOption() throws IOException {
 
         return expression;
     }
+
+    /**
+     * 사용자의 입력을 받아 반환하는 함수
+     *
+     * @return 사용자가 입력한 문자열
+     * @throws IOException
+     */
+    public String getInput() throws IOException {
+        return br.readLine();
+    }
 }
\ No newline at end of file

From 42c01e7f73db6b130045aeb6f5c2c47aa48c3cc3 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 17:53:20 +0900
Subject: [PATCH 06/19] =?UTF-8?q?feat:=20=EC=9E=98=EB=AA=BB=EB=90=9C=20?=
 =?UTF-8?q?=EC=9E=85=EB=A0=A5=EC=9D=84=20=EC=B2=98=EB=A6=AC=ED=95=98?=
 =?UTF-8?q?=EB=8A=94=20=EA=B8=B0=EB=8A=A5?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../main/java/com/programmers/io/IOConsole.java    | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/app/src/main/java/com/programmers/io/IOConsole.java b/app/src/main/java/com/programmers/io/IOConsole.java
index e51c2f37d..68e9be388 100644
--- a/app/src/main/java/com/programmers/io/IOConsole.java
+++ b/app/src/main/java/com/programmers/io/IOConsole.java
@@ -9,6 +9,9 @@ public class IOConsole {
     private static final String HISTORY_OPTION_MESSAGE = "1. 조회";
     private static final String CALCULATE_OPTION_MESSAGE = "2. 계산";
     private static final String USER_CHOICE_MESSAGE = "선택 : ";
+    // 오류 발생 메시지
+    private static final String WRONG_OPTION_MESSAGE = "계산기에서 지원하지 않는 옵션입니다.";
+    private static final String SHUTDOWN_MESSAGE = "계산기를 종료합니다.";
     private static final BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
 
     /**
@@ -43,4 +46,15 @@ public String getOption() throws IOException {
     public String getInput() throws IOException {
         return br.readLine();
     }
+
+    /**
+     * 잘못된 선택 입력이 들어왔을 때 처리하는 메소드
+     *
+     * @throws IOException
+     */
+    public void handleWrongInput() throws IOException {
+        System.out.println(WRONG_OPTION_MESSAGE);
+        System.out.println(SHUTDOWN_MESSAGE);
+        br.close();
+    }
 }
\ No newline at end of file

From 7786b09c10b622581ac1a0f38b3252f549748a89 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 17:53:57 +0900
Subject: [PATCH 07/19] =?UTF-8?q?feat:=20=EA=B3=84=EC=82=B0=EC=9D=98=20?=
 =?UTF-8?q?=EA=B2=B0=EA=B3=BC=EB=A5=BC=20=EC=B6=9C=EB=A0=A5=ED=95=98?=
 =?UTF-8?q?=EB=8A=94=20=EA=B8=B0=EB=8A=A5?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 app/src/main/java/com/programmers/io/IOConsole.java | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/app/src/main/java/com/programmers/io/IOConsole.java b/app/src/main/java/com/programmers/io/IOConsole.java
index 68e9be388..484aa69d9 100644
--- a/app/src/main/java/com/programmers/io/IOConsole.java
+++ b/app/src/main/java/com/programmers/io/IOConsole.java
@@ -57,4 +57,15 @@ public void handleWrongInput() throws IOException {
         System.out.println(SHUTDOWN_MESSAGE);
         br.close();
     }
+
+    /**
+     * 계산의 결과를 출력하는 함수
+     *
+     * @param answer 계산의 결과
+     */
+    public void printAnswer(double answer) {
+        System.out.printf("%.2f", answer);
+        System.out.println();
+        System.out.println();
+    }
 }
\ No newline at end of file

From 11744a77e5087cf87176abcfbe40e064a82318e7 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 17:54:18 +0900
Subject: [PATCH 08/19] =?UTF-8?q?feat:=20=EB=AC=B8=EC=9E=90=EC=97=B4?=
 =?UTF-8?q?=EC=9D=84=20=EC=B6=9C=EB=A0=A5=ED=95=98=EB=8A=94=20=EA=B8=B0?=
 =?UTF-8?q?=EB=8A=A5?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 app/src/main/java/com/programmers/io/IOConsole.java | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/app/src/main/java/com/programmers/io/IOConsole.java b/app/src/main/java/com/programmers/io/IOConsole.java
index 484aa69d9..b7cfc3d1a 100644
--- a/app/src/main/java/com/programmers/io/IOConsole.java
+++ b/app/src/main/java/com/programmers/io/IOConsole.java
@@ -68,4 +68,13 @@ public void printAnswer(double answer) {
         System.out.println();
         System.out.println();
     }
+
+    /**
+     * 문자열을 출력하는 함수
+     *
+     * @param s 문자열
+     */
+    public void print(String s) {
+        System.out.println(s);
+    }
 }
\ No newline at end of file

From 1c2a57469997afbaa521682a585a2fcdcf21cdc7 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 17:54:55 +0900
Subject: [PATCH 09/19] =?UTF-8?q?feat:=20=EC=82=AC=EC=9A=A9=EC=9E=90?=
 =?UTF-8?q?=EA=B0=80=20=EC=9E=85=EB=A0=A5=ED=95=9C=20=EA=B3=84=EC=82=B0?=
 =?UTF-8?q?=EC=8B=9D=EC=9D=84=20=EA=B2=80=EC=A6=9D=ED=95=98=EB=8A=94=20?=
 =?UTF-8?q?=EA=B8=B0=EB=8A=A5?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../java/com/programmers/io/IOConsole.java    | 21 +++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/app/src/main/java/com/programmers/io/IOConsole.java b/app/src/main/java/com/programmers/io/IOConsole.java
index b7cfc3d1a..bc17e7b8d 100644
--- a/app/src/main/java/com/programmers/io/IOConsole.java
+++ b/app/src/main/java/com/programmers/io/IOConsole.java
@@ -9,9 +9,15 @@ public class IOConsole {
     private static final String HISTORY_OPTION_MESSAGE = "1. 조회";
     private static final String CALCULATE_OPTION_MESSAGE = "2. 계산";
     private static final String USER_CHOICE_MESSAGE = "선택 : ";
+
     // 오류 발생 메시지
+    private static final String WRONG_INPUT_MESSAGE = "계산기에서 지원하지 않는 입력입니다.";
     private static final String WRONG_OPTION_MESSAGE = "계산기에서 지원하지 않는 옵션입니다.";
     private static final String SHUTDOWN_MESSAGE = "계산기를 종료합니다.";
+
+    // 사용자의 입력을 검증하는 regex. 사칙연산자와 숫자, 공백 문자열을 허용한다.
+    private static final String INPUT_REGEX = "^[\\d\\+\\-\\*/\\(\\)\\s]+$";
+
     private static final BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
 
     /**
@@ -77,4 +83,19 @@ public void printAnswer(double answer) {
     public void print(String s) {
         System.out.println(s);
     }
+
+    /**
+     * 사용자의 input을 검증하는 메소드.
+     *
+     * @param inputExpression 사용자가 입력한 중위 표현식
+     * @return true or false
+     */
+    public boolean validateInputExpression(String inputExpression) {
+        if (!inputExpression.matches(INPUT_REGEX)) {
+            System.out.println(WRONG_INPUT_MESSAGE + "\n");
+            return false;
+        }
+
+        return true;
+    }
 }
\ No newline at end of file

From 350b19ac30e0300ec248ce507c15cb1586102329 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 17:56:51 +0900
Subject: [PATCH 10/19] =?UTF-8?q?feat:=20=EA=B3=84=EC=82=B0=20=EC=9D=B4?=
 =?UTF-8?q?=EB=A0=A5=EC=9D=84=20=EC=A0=80=EC=9E=A5=ED=95=98=EB=8A=94=20?=
 =?UTF-8?q?=ED=81=B4=EB=9E=98=EC=8A=A4=20=EC=A0=95=EC=9D=98?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../java/com/programmers/memory/HistoryMemory.java  | 13 +++++++++++++
 1 file changed, 13 insertions(+)
 create mode 100644 app/src/main/java/com/programmers/memory/HistoryMemory.java

diff --git a/app/src/main/java/com/programmers/memory/HistoryMemory.java b/app/src/main/java/com/programmers/memory/HistoryMemory.java
new file mode 100644
index 000000000..541346ea1
--- /dev/null
+++ b/app/src/main/java/com/programmers/memory/HistoryMemory.java
@@ -0,0 +1,13 @@
+package com.programmers.memory;
+
+import java.util.*;
+
+public class HistoryMemory {
+    private Map<Integer, String> historyMemoryMap;
+    private int orderNumber;
+
+    public HistoryMemory() {
+        this.historyMemoryMap = new HashMap<>();
+        this.orderNumber = 0;
+    }
+}
\ No newline at end of file

From df8112bad47a1b61f3f4acb8d70ca6048e3e5cf6 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 17:57:38 +0900
Subject: [PATCH 11/19] =?UTF-8?q?feat:=20=EC=82=AC=EC=9A=A9=EC=9E=90?=
 =?UTF-8?q?=EA=B0=80=20=EC=9E=85=EB=A0=A5=ED=95=9C=20=ED=91=9C=ED=98=84?=
 =?UTF-8?q?=EC=8B=9D=EC=9D=84=20=EC=A0=80=EC=9E=A5=ED=95=98=EB=8A=94=20?=
 =?UTF-8?q?=EA=B8=B0=EB=8A=A5?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../java/com/programmers/memory/HistoryMemory.java    | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/app/src/main/java/com/programmers/memory/HistoryMemory.java b/app/src/main/java/com/programmers/memory/HistoryMemory.java
index 541346ea1..62257e1b0 100644
--- a/app/src/main/java/com/programmers/memory/HistoryMemory.java
+++ b/app/src/main/java/com/programmers/memory/HistoryMemory.java
@@ -10,4 +10,15 @@ public HistoryMemory() {
         this.historyMemoryMap = new HashMap<>();
         this.orderNumber = 0;
     }
+
+    /**
+     * 사용자가 입력한 중위 표현식을 저장하는 메소드
+     *
+     * @param inputExpression 사용자가 입력한 중위 표현식
+     * @param result 계산 결과
+     */
+    public void saveHistory(String inputExpression, double result) {
+        String formatExpression = String.format("%s = %.2f", inputExpression, result);
+        historyMemoryMap.put(++orderNumber, formatExpression);
+    }
 }
\ No newline at end of file

From 5a33909aaee561cfdc9c8b2e5eb68e2f50c2ba72 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 17:58:07 +0900
Subject: [PATCH 12/19] =?UTF-8?q?feat:=20=EA=B3=84=EC=82=B0=20=EC=9D=B4?=
 =?UTF-8?q?=EB=A0=A5=EC=9D=84=20=EA=B0=80=EC=A0=B8=EC=98=A4=EB=8A=94=20?=
 =?UTF-8?q?=EA=B8=B0=EB=8A=A5?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../com/programmers/memory/HistoryMemory.java | 20 +++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/app/src/main/java/com/programmers/memory/HistoryMemory.java b/app/src/main/java/com/programmers/memory/HistoryMemory.java
index 62257e1b0..e5cb81d30 100644
--- a/app/src/main/java/com/programmers/memory/HistoryMemory.java
+++ b/app/src/main/java/com/programmers/memory/HistoryMemory.java
@@ -21,4 +21,24 @@ public void saveHistory(String inputExpression, double result) {
         String formatExpression = String.format("%s = %.2f", inputExpression, result);
         historyMemoryMap.put(++orderNumber, formatExpression);
     }
+
+    /**
+     * 계산 이력을 가져오는 메소드
+     *
+     * @return 계산 이력
+     */
+    public String getHistory() {
+        StringBuilder sb = new StringBuilder();
+        List<Integer> keyList = new ArrayList<>(historyMemoryMap.keySet());
+
+        Collections.sort(keyList);
+
+        for (int key : keyList) {
+            sb.append(historyMemoryMap.get(key) + "\n");
+        }
+
+        String history = sb.toString();
+
+        return history;
+    }
 }
\ No newline at end of file

From 5bb19931e641db0418407487999d3b330df31d01 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 18:05:36 +0900
Subject: [PATCH 13/19] =?UTF-8?q?feat:=20=EC=A4=91=EC=9C=84=20=ED=91=9C?=
 =?UTF-8?q?=ED=98=84=EC=8B=9D=EC=9D=84=20=EA=B2=80=EC=A6=9D=ED=95=98?=
 =?UTF-8?q?=EB=8A=94=20=EA=B8=B0=EB=8A=A5?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../programmers/calculator/Calculator.java    | 95 +++++++++++++++++++
 1 file changed, 95 insertions(+)
 create mode 100644 app/src/main/java/com/programmers/calculator/Calculator.java

diff --git a/app/src/main/java/com/programmers/calculator/Calculator.java b/app/src/main/java/com/programmers/calculator/Calculator.java
new file mode 100644
index 000000000..a0dd471d7
--- /dev/null
+++ b/app/src/main/java/com/programmers/calculator/Calculator.java
@@ -0,0 +1,95 @@
+package com.programmers.calculator;
+
+import java.util.ArrayDeque;
+import java.util.Deque;
+
+public class Calculator {
+    // 사칙 연산자
+    private static final String ADD_OPERATOR = "+";
+    private static final String SUBTRACTION_OPERATOR = "-";
+    private static final String MULTIPLY_OPERATOR = "*";
+    private static final String DIVIDE_OPERATOR = "/";
+
+    // 괄호
+    private static final String OPEN_BRACKET = "(";
+    private static final String CLOSE_BRACKET = ")";
+
+    // 중위 표현식 검증 regex
+    private static final String EXPRESSION_REGEX = "(?<=[-+*/()])|(?=[-+*/()])";    // 정수, 괄호, 연산자들을 구분한다.
+    private static final String CONSECUTIVE_OPERATORS_REGEX = ".*[\\+\\-\\*/]{2,}.*";   // 반복되는 연산자를 검증한다.
+
+    // 중위 표현식 오류 메시지
+    private static final String WRONG_INFIX_EXPRESSION_MESSAGE = "중위 표현식이 유효하지 않습니다.";
+    /**
+     * 중위 표현식이 유효한지 검증하는 메소드
+     *
+     * @param inputExpression 사용자에게 입력받은 중위 표현식
+     * @return 검증이 완료된 표현식
+     * @throws IllegalArgumentException
+     */
+    private String validateInfixExpression(String inputExpression) throws IllegalArgumentException {
+        String blankRemovedExpression = inputExpression.replace(" ", "");
+
+        String[] expressionTokens = blankRemovedExpression.split(EXPRESSION_REGEX);
+
+        validateBracket(expressionTokens);
+
+        validateOperandAndOperatorNumber(expressionTokens);
+
+        validateConsecutiveOperators(blankRemovedExpression);
+
+        return blankRemovedExpression;
+    }
+
+    /**
+     * 중위 표현식에서 괄호의 갯수를 검증하는 메소드
+     *
+     * @param expressionTokens 표현식 조각으로 이루어진 토큰 배열
+     * @throws IllegalArgumentException
+     */
+    private void validateBracket(String[] expressionTokens) throws IllegalArgumentException {
+        Deque<String> tokenStack = new ArrayDeque<>();
+
+        for (String token : expressionTokens) {
+            switch (token) {
+                case OPEN_BRACKET: {
+                    tokenStack.push(token);
+                    break;
+                }
+                case CLOSE_BRACKET: {
+                    if (tokenStack.isEmpty()) {
+                        throw new IllegalArgumentException(WRONG_INFIX_EXPRESSION_MESSAGE);
+                    }
+                    tokenStack.pop();
+                }
+            }
+        }
+
+        if (!tokenStack.isEmpty()) {
+            throw new IllegalArgumentException(WRONG_INFIX_EXPRESSION_MESSAGE);
+        }
+    }
+
+    /**
+     * 연산자가 연속하는지 검증하는 메소드
+     *
+     * @param expression 표현식
+     * @throws IllegalArgumentException
+     */
+    private void validateConsecutiveOperators(String expression) throws IllegalArgumentException {
+        if (expression.matches(CONSECUTIVE_OPERATORS_REGEX)) {
+            throw new IllegalArgumentException(WRONG_INFIX_EXPRESSION_MESSAGE);
+        }
+    }
+
+    /**
+     * 연산자와 피연산자의 갯수 검증하는 메소드.
+     *
+     * @param tokens 표현식 토큰
+     */
+    private void validateOperandAndOperatorNumber(String[] tokens) {
+        if (tokens.length % 2 != 1) {   // 중위 표현식의 토큰 갯수는 항상 홀수임을 이용함(피연산자의 개수 = 연산자의 갯수 + 1).
+            throw new IllegalArgumentException(WRONG_INFIX_EXPRESSION_MESSAGE);
+        }
+    }
+}
\ No newline at end of file

From b20e83153cbec12d219267a53c5ae50ec0907056 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 18:06:13 +0900
Subject: [PATCH 14/19] =?UTF-8?q?feat:=20=EC=A4=91=EC=9C=84=20=ED=91=9C?=
 =?UTF-8?q?=ED=98=84=EC=8B=9D=EC=9D=84=20=ED=9B=84=EC=9C=84=20=ED=91=9C?=
 =?UTF-8?q?=ED=98=84=EC=8B=9D=EC=9C=BC=EB=A1=9C=20=EB=B3=80=ED=99=98?=
 =?UTF-8?q?=ED=95=98=EB=8A=94=20=EA=B8=B0=EB=8A=A5?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../programmers/calculator/Calculator.java    | 53 +++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/app/src/main/java/com/programmers/calculator/Calculator.java b/app/src/main/java/com/programmers/calculator/Calculator.java
index a0dd471d7..9db7a4173 100644
--- a/app/src/main/java/com/programmers/calculator/Calculator.java
+++ b/app/src/main/java/com/programmers/calculator/Calculator.java
@@ -20,6 +20,59 @@ public class Calculator {
 
     // 중위 표현식 오류 메시지
     private static final String WRONG_INFIX_EXPRESSION_MESSAGE = "중위 표현식이 유효하지 않습니다.";
+
+    /**
+     * 중위 표현식을 후위 표현식으로 변환하는 메소드
+     *
+     * @param inputExpression 사용자에게 입력받은 중위 표현식
+     * @return postfixExpression 변환된 후위 표기식
+     * @throws IllegalArgumentException
+     */
+    public String convert(String inputExpression) throws IllegalArgumentException {
+        StringBuilder sb = new StringBuilder();
+        Deque<String> infixStack = new ArrayDeque<>();
+
+        String validExpression = validateInfixExpression(inputExpression);
+        String[] expressionTokens = validExpression.split(EXPRESSION_REGEX);
+
+        for (String token : expressionTokens) {
+            switch (token) {
+                case ADD_OPERATOR:
+                case SUBTRACTION_OPERATOR:
+                case MULTIPLY_OPERATOR:
+                case DIVIDE_OPERATOR: {
+                    while (!infixStack.isEmpty() && priority(infixStack.peek()) >= priority(token)) {
+                        sb.append(infixStack.pop() + " ");
+                    }
+                    infixStack.push(token);
+                    break;
+                }
+                case OPEN_BRACKET: {
+                    infixStack.push(token);
+                    break;
+                }
+                case CLOSE_BRACKET: {
+                    while (!infixStack.isEmpty() && !infixStack.peek().equals(OPEN_BRACKET)) {
+                        sb.append(infixStack.pop() + " ");
+                    }
+                    infixStack.pop();
+                    break;
+                }
+                default: {
+                    sb.append(token + " ");
+                }
+            }
+        }
+
+        while (!infixStack.isEmpty()) {
+            sb.append(infixStack.pop() + " ");
+        }
+
+        sb.delete(sb.length() - 1, sb.length());
+        String postfixExpression = sb.toString();
+
+        return postfixExpression;
+    }
     /**
      * 중위 표현식이 유효한지 검증하는 메소드
      *

From 64add595321377129445051e8145e5c7828da43a Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Sun, 11 Jun 2023 18:06:48 +0900
Subject: [PATCH 15/19] =?UTF-8?q?feat:=20=ED=9B=84=EC=9C=84=20=ED=91=9C?=
 =?UTF-8?q?=EA=B8=B0=EC=8B=9D=EC=9D=84=20=EA=B8=B0=EB=B0=98=EC=9C=BC?=
 =?UTF-8?q?=EB=A1=9C=20=EA=B3=84=EC=82=B0=ED=95=98=EB=8A=94=20=EA=B8=B0?=
 =?UTF-8?q?=EB=8A=A5?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../programmers/calculator/Calculator.java    | 70 +++++++++++++++++++
 1 file changed, 70 insertions(+)

diff --git a/app/src/main/java/com/programmers/calculator/Calculator.java b/app/src/main/java/com/programmers/calculator/Calculator.java
index 9db7a4173..0d0a11234 100644
--- a/app/src/main/java/com/programmers/calculator/Calculator.java
+++ b/app/src/main/java/com/programmers/calculator/Calculator.java
@@ -73,6 +73,76 @@ public String convert(String inputExpression) throws IllegalArgumentException {
 
         return postfixExpression;
     }
+
+    /**
+     * 후위 표기식의 계산 결과를 반환하는 메소드
+     *
+     * @param postfixExpression
+     * @return 연산의 결과
+     * @throws ArithmeticException
+     */
+    public double calculate(String postfixExpression) throws ArithmeticException {
+        Deque<String> postfixStack = new ArrayDeque<>();
+
+        for (String postfixToken : postfixExpression.split(" ")) {
+            if (isOperator(postfixToken)) {
+                double y = Double.parseDouble(postfixStack.pop());
+                double x = Double.parseDouble(postfixStack.pop());
+
+                switch (postfixToken) {
+                    case ADD_OPERATOR: {
+                        postfixStack.push(String.format("%.2f", x + y));
+                        break;
+                    }
+                    case SUBTRACTION_OPERATOR: {
+                        postfixStack.push(String.format("%.2f", x - y));
+                        break;
+                    }
+                    case MULTIPLY_OPERATOR: {
+                        postfixStack.push(String.format("%.2f", x * y));
+                        break;
+                    }
+                    case DIVIDE_OPERATOR: {
+                        postfixStack.push(String.format("%.2f", x / y));
+                    }
+                }
+            } else {
+                postfixStack.push(postfixToken);
+            }
+        }
+
+        return Double.parseDouble(postfixStack.pop());
+    }
+
+    /**
+     * 사칙연산자인지 확인하는 메소드
+     *
+     * @param token
+     * @return true or false
+     */
+    private boolean isOperator(String token) {
+        return token.equals(ADD_OPERATOR) || token.equals(SUBTRACTION_OPERATOR) || token.equals(MULTIPLY_OPERATOR) || token.equals(DIVIDE_OPERATOR);
+    }
+
+    /**
+     * 연산자의 우선순위를 판별하는 메소드
+     *
+     * @param operator 연산자
+     * @return 우선순위
+     */
+    private int priority(String operator) {
+        if (operator.equals(OPEN_BRACKET) || operator.equals(CLOSE_BRACKET)) {
+            return 0;
+        }
+        if (operator.equals(ADD_OPERATOR) || operator.equals(SUBTRACTION_OPERATOR)) {
+            return 1;
+        }
+        if (operator.equals(MULTIPLY_OPERATOR) || operator.equals(DIVIDE_OPERATOR)) {
+            return 2;
+        }
+        return -1;
+    }
+
     /**
      * 중위 표현식이 유효한지 검증하는 메소드
      *

From ee9ab37e6f2f82498c1340be09d9e389cc6bf2c6 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Tue, 13 Jun 2023 02:25:56 +0900
Subject: [PATCH 16/19] =?UTF-8?q?refactor:=20=EA=B3=84=EC=82=B0=EA=B8=B0?=
 =?UTF-8?q?=20=EB=8F=99=EC=9E=91=EC=9D=84=20=EB=8B=B4=EB=8B=B9=ED=95=98?=
 =?UTF-8?q?=EB=8A=94=20controller=20=EC=B6=94=EA=B0=80?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 app/src/main/java/com/programmers/App.java    | 53 ++--------------
 .../contoller/CalculatorController.java       | 63 +++++++++++++++++++
 2 files changed, 67 insertions(+), 49 deletions(-)
 create mode 100644 app/src/main/java/com/programmers/contoller/CalculatorController.java

diff --git a/app/src/main/java/com/programmers/App.java b/app/src/main/java/com/programmers/App.java
index ffb0437d2..8528510f9 100644
--- a/app/src/main/java/com/programmers/App.java
+++ b/app/src/main/java/com/programmers/App.java
@@ -3,58 +3,13 @@
  */
 package com.programmers;
 
-import com.programmers.calculator.Calculator;
-import com.programmers.io.IOConsole;
-import com.programmers.memory.HistoryMemory;
+import com.programmers.contoller.CalculatorController;
 
-import java.io.*;
+import java.io.IOException;
 
 public class App {
-    // 계산기 옵션
-    private static final String SHOW_HISTORY_OPTION = "1";
-    private static final String CALCULATE_OPTION = "2";
-
-    private static final IOConsole ioConsole = new IOConsole(); // 입출력 콘솔
-    private static final Calculator calculator = new Calculator();  // 숫자 계산을 담당하는 부분
-    private static final HistoryMemory historyMemory = new HistoryMemory(); // 계산 결과 메모리
-
     public static void main(String[] args) throws IOException {
-        while (true) {
-            ioConsole.printMenu();
-
-            String option = ioConsole.getOption();
-
-            switch (option) {
-                case SHOW_HISTORY_OPTION: {  // 1. 조회
-                    String history = historyMemory.getHistory();
-                    ioConsole.print(history);
-                    break;
-                }
-                case CALCULATE_OPTION: {  // 2. 계산
-                    String inputExpression = ioConsole.getInput();
-
-                    if (!ioConsole.validateInputExpression(inputExpression)) {
-                        break;
-                    }
-
-                    try {
-                        String convertedExpression = calculator.convert(inputExpression);
-
-                        double answer = calculator.calculate(convertedExpression);
-
-                        historyMemory.saveHistory(inputExpression, answer);
-
-                        ioConsole.printAnswer(answer);
-                    } catch (Exception e) {
-                        ioConsole.print(e.getMessage() + "\n");
-                    }
-                    break;
-                }
-                default: {  // 잘못된 입력을 처리
-                    ioConsole.handleWrongInput();
-                    return;
-                }
-            }
-        }
+        CalculatorController calculatorController = new CalculatorController();
+        calculatorController.run();
     }
 }
\ No newline at end of file
diff --git a/app/src/main/java/com/programmers/contoller/CalculatorController.java b/app/src/main/java/com/programmers/contoller/CalculatorController.java
new file mode 100644
index 000000000..ca95da1f8
--- /dev/null
+++ b/app/src/main/java/com/programmers/contoller/CalculatorController.java
@@ -0,0 +1,63 @@
+package com.programmers.contoller;
+
+import com.programmers.calculator.Calculator;
+import com.programmers.io.IOConsole;
+import com.programmers.memory.HistoryMemory;
+
+import java.io.IOException;
+
+public class CalculatorController {
+    // 계산기 옵션
+    private static final String SHOW_HISTORY_OPTION = "1";
+    private static final String CALCULATE_OPTION = "2";
+
+    private static IOConsole ioConsole;
+    private static Calculator calculator;
+    private static HistoryMemory historyMemory;
+
+    public CalculatorController() {
+        ioConsole = new IOConsole(); // 입출력 콘솔
+        calculator = new Calculator();  // 숫자 계산을 담당하는 부분
+        historyMemory = new HistoryMemory(); // 계산 결과 메모리
+    }
+
+    public void run() throws IOException {
+        while (true) {
+            ioConsole.printMenu();
+
+            String option = ioConsole.getOption();
+
+            switch (option) {
+                case SHOW_HISTORY_OPTION: {  // 1. 조회
+                    String history = historyMemory.getHistory();
+                    ioConsole.print(history);
+                    break;
+                }
+                case CALCULATE_OPTION: {  // 2. 계산
+                    String inputExpression = ioConsole.getInput();
+
+                    if (!ioConsole.validateInputExpression(inputExpression)) {
+                        break;
+                    }
+
+                    try {
+                        String convertedExpression = calculator.convert(inputExpression);
+
+                        double answer = calculator.calculate(convertedExpression);
+
+                        historyMemory.saveHistory(inputExpression, answer);
+
+                        ioConsole.printAnswer(answer);
+                    } catch (Exception e) {
+                        ioConsole.print(e.getMessage() + "\n");
+                    }
+                    break;
+                }
+                default: {  // 잘못된 입력을 처리
+                    ioConsole.handleWrongInput();
+                    return;
+                }
+            }
+        }
+    }
+}

From bfcfb870f68a961089175f03f27c1f19333e7300 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Tue, 13 Jun 2023 02:27:22 +0900
Subject: [PATCH 17/19] =?UTF-8?q?test:=20=EC=9E=85=EC=B6=9C=EB=A0=A5=20?=
 =?UTF-8?q?=EA=B4=80=EB=A0=A8=20test=20=EC=B6=94=EA=B0=80?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../com/programmers/io/IOConsoleTest.java     | 65 +++++++++++++++++++
 1 file changed, 65 insertions(+)
 create mode 100644 app/src/test/java/com/programmers/io/IOConsoleTest.java

diff --git a/app/src/test/java/com/programmers/io/IOConsoleTest.java b/app/src/test/java/com/programmers/io/IOConsoleTest.java
new file mode 100644
index 000000000..fd0daa8ec
--- /dev/null
+++ b/app/src/test/java/com/programmers/io/IOConsoleTest.java
@@ -0,0 +1,65 @@
+package com.programmers.io;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.io.*;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class IOConsoleTest {
+    private static final String HISTORY_OPTION_MESSAGE = "1. 조회";
+    private static final String CALCULATE_OPTION_MESSAGE = "2. 계산";
+
+    private static IOConsole ioConsole;
+    private static OutputStream out;
+
+    @BeforeEach
+    void initAll() {
+        ioConsole = new IOConsole(); // 입출력 콘솔
+
+        // 표준 출력 설정
+        out = new ByteArrayOutputStream();
+        System.setOut(new PrintStream(out));
+    }
+
+    @Test
+    void printMenuTest() {
+        ioConsole.printMenu();
+
+        assertEquals(HISTORY_OPTION_MESSAGE + "\n" + CALCULATE_OPTION_MESSAGE + "\n\n", out.toString());
+    }
+
+    @Test
+    void printAnswerTest() {
+        double answer = 3.141592;
+
+        ioConsole.printAnswer(answer);
+
+        assertEquals("3.14\n\n", out.toString());
+    }
+
+    @Test
+    void validateInputExpressionTest() {
+        String expression1 = "1 +2";
+        String expression2 = "1 * 2";
+        String expression3 = "1 $2";
+        String expression4 = " 12 - 1";
+        String expression5 = "1 &2";
+        String expression6 = "1 /2";
+
+        boolean result1 = ioConsole.validateInputExpression(expression1);
+        boolean result2 = ioConsole.validateInputExpression(expression2);
+        boolean result3 = ioConsole.validateInputExpression(expression3);
+        boolean result4 = ioConsole.validateInputExpression(expression4);
+        boolean result5 = ioConsole.validateInputExpression(expression5);
+        boolean result6 = ioConsole.validateInputExpression(expression6);
+
+        assertEquals(true, result1);
+        assertEquals(true, result2);
+        assertEquals(false, result3);
+        assertEquals(true, result4);
+        assertEquals(false, result5);
+        assertEquals(true, result6);
+    }
+}

From 71ebf728acabd34f596474c6cf37fe9404f47e0c Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Tue, 13 Jun 2023 02:27:33 +0900
Subject: [PATCH 18/19] =?UTF-8?q?test:=20=EB=A9=94=EB=AA=A8=EB=A6=AC=20?=
 =?UTF-8?q?=EA=B4=80=EB=A0=A8=20test=20=EC=B6=94=EA=B0=80?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../programmers/memory/HistoryMemoryTest.java | 29 +++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 app/src/test/java/com/programmers/memory/HistoryMemoryTest.java

diff --git a/app/src/test/java/com/programmers/memory/HistoryMemoryTest.java b/app/src/test/java/com/programmers/memory/HistoryMemoryTest.java
new file mode 100644
index 000000000..b4bfd30e3
--- /dev/null
+++ b/app/src/test/java/com/programmers/memory/HistoryMemoryTest.java
@@ -0,0 +1,29 @@
+package com.programmers.memory;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class HistoryMemoryTest {
+    static final HistoryMemory historyMemory = new HistoryMemory(); // 계산 결과 메모리
+
+    @Test
+    void memoryTest() {
+        String inputExpression1 = "1 + 2";
+        String inputExpression2 = "1 + 2 * 3";
+        String inputExpression3 = "3 - 2 * 2";
+
+        historyMemory.saveHistory(inputExpression1, 3);
+        historyMemory.saveHistory(inputExpression2, 7);
+        historyMemory.saveHistory(inputExpression3, -1);
+
+
+        String history = historyMemory.getHistory();
+
+        String expectedHistory1 = inputExpression1 + " = 3.00\n";
+        String expectedHistory2 = inputExpression2 + " = 7.00\n";
+        String expectedHistory3 = inputExpression3 + " = -1.00\n";
+
+        assertEquals(expectedHistory1 + expectedHistory2 + expectedHistory3, history);
+    }
+}

From c3ccd020a9b2cc417b0d21f0fb9f3e2d8eb421e9 Mon Sep 17 00:00:00 2001
From: hi-june <wnsgur735@gmail.com>
Date: Tue, 13 Jun 2023 02:28:03 +0900
Subject: [PATCH 19/19] =?UTF-8?q?test:=20calculator=20=EA=B4=80=EB=A0=A8?=
 =?UTF-8?q?=20test=20=EC=B6=94=EA=B0=80?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../calculator/CalculatorTest.java            | 86 +++++++++++++++++++
 1 file changed, 86 insertions(+)
 create mode 100644 app/src/test/java/com/programmers/calculator/CalculatorTest.java

diff --git a/app/src/test/java/com/programmers/calculator/CalculatorTest.java b/app/src/test/java/com/programmers/calculator/CalculatorTest.java
new file mode 100644
index 000000000..9dbd9a421
--- /dev/null
+++ b/app/src/test/java/com/programmers/calculator/CalculatorTest.java
@@ -0,0 +1,86 @@
+package com.programmers.calculator;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class CalculatorTest {
+    static Calculator calculator;
+
+    @BeforeEach
+    void initAll() {
+        calculator = new Calculator();
+    }
+
+    @Test
+    void convertValidExpressionTest() {
+        String inputExpression1 = "1 + 2";
+        String inputExpression2 = "1 + 2 * 3";
+        String inputExpression3 = "3 - 2 * 2";
+        String inputExpression4 = "2 * (30 - 2) + 2";
+
+        String convertedExpression1 = calculator.convert(inputExpression1);
+        String convertedExpression2 = calculator.convert(inputExpression2);
+        String convertedExpression3 = calculator.convert(inputExpression3);
+        String convertedExpression4 = calculator.convert(inputExpression4);
+
+        String postfixExpression1 = "1 2 +";
+        String postfixExpression2 = "1 2 3 * +";
+        String postfixExpression3 = "3 2 2 * -";
+        String postfixExpression4 = "2 30 2 - * 2 +";
+
+        assertEquals(postfixExpression1, convertedExpression1);
+        assertEquals(postfixExpression2, convertedExpression2);
+        assertEquals(postfixExpression3, convertedExpression3);
+        assertEquals(postfixExpression4, convertedExpression4);
+    }
+
+    @Test
+    void convertInValidExpressionTest() {
+        String inputExpression1 = "2 * ((30 - 2) + 2";  // 괄호의 갯수 검증
+        String inputExpression2 = "2 * )30 - 2( + 2";   // 괄호 순서 검증
+        String inputExpression3 = "3 -+ 2 * 2"; // 연산자 연속성 검증
+        String inputExpression4 = "2 * 30 - 2 +";   // 연산자, 피연산자 갯수 검증
+
+        Assertions.assertThrows(IllegalArgumentException.class, () -> {
+            calculator.convert(inputExpression1);
+        });
+
+        Assertions.assertThrows(IllegalArgumentException.class, () -> {
+            calculator.convert(inputExpression2);
+        });
+
+        Assertions.assertThrows(IllegalArgumentException.class, () -> {
+            calculator.convert(inputExpression3);
+        });
+
+        Assertions.assertThrows(IllegalArgumentException.class, () -> {
+            calculator.convert(inputExpression4);
+        });
+    }
+
+    @Test
+    void calculateTest() {
+        String postfixExpression1 = "1 2 +";
+        String postfixExpression2 = "1 2 3 * +";
+        String postfixExpression3 = "3 2 2 * -";
+        String postfixExpression4 = "2 30 2 - * 2 +";
+
+        double result1 = calculator.calculate(postfixExpression1);
+        double result2 = calculator.calculate(postfixExpression2);
+        double result3 = calculator.calculate(postfixExpression3);
+        double result4 = calculator.calculate(postfixExpression4);
+
+        double answer1 = 1 + 2;
+        double answer2 = 1 + (2 * 3);
+        double answer3 = 3 - (2 * 2);
+        double answer4 = 2 * (30 - 2) + 2;
+
+        assertEquals(answer1, result1);
+        assertEquals(answer2, result2);
+        assertEquals(answer3, result3);
+        assertEquals(answer4, result4);
+    }
+}