Small API updates

Author: Artem Labazin

CHANGELOG.md

@@ -12,6 +12,17 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Add more tests.
 - Add `JavaDoc`.
 
+## [1.13.1](https://github.com/appulse-projects/utils-java/releases/tag/1.13.1) - 2019-04-08
+
+### Added
+
+- `Bytes`.`capacity(int)` method for resizing buffers.
+
+### Changed
+
+- Added static methods for `BytesByteBuf` wrapper;
+- Concrete Java version (1.8) now specified in `pom.xml`.
+
 ## [1.13.0](https://github.com/appulse-projects/utils-java/releases/tag/1.13.0) - 2019-04-07
 
 ### Changed

pom.xml

@@ -24,14 +24,14 @@ limitations under the License.
 
   <groupId>io.appulse</groupId>
   <artifactId>utils-java</artifactId>
-  <version>1.13.0</version>
+  <version>1.13.1</version>
   <packaging>jar</packaging>
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.build.resourceEncoding>UTF-8</project.build.resourceEncoding>
 
-    <java.version>${java.vm.specification.version}</java.version>
+    <java.version>1.8</java.version>
 
     <maven.compiler.source>${java.version}</maven.compiler.source>
     <maven.compiler.target>${java.version}</maven.compiler.target>
@@ -66,7 +66,7 @@ limitations under the License.
     <url>https://github.com/appulse-projects/utils-java</url>
     <connection>scm:git:https://github.com/appulse-projects/utils-java.git</connection>
     <developerConnection>scm:git:https://github.com/appulse-projects/utils-java.git</developerConnection>
-    <tag>1.13.0</tag>
+    <tag>1.13.1</tag>
   </scm>
 
   <distributionManagement>

src/main/java/io/appulse/utils/Bytes.java

@@ -1641,6 +1641,13 @@ static Bytes resizableArray (int initialSize) {
    */
   int capacity ();
 
+  /**
+   * Extends or reduces the buffer's capacity.
+   *
+   * @param bytes the new buffer's capacity
+   */
+  void capacity (int bytes);
+
   /**
    * Returns the {@code writerIndex} of this buffer.
    *

src/main/java/io/appulse/utils/BytesByteBuf.java

@@ -16,30 +16,66 @@
 
 package io.appulse.utils;
 
-import static lombok.AccessLevel.PACKAGE;
 import static lombok.AccessLevel.PRIVATE;
 
+import java.nio.ByteBuffer;
 import java.nio.charset.Charset;
+import java.util.Arrays;
 
 import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
 import lombok.NonNull;
-import lombok.RequiredArgsConstructor;
 import lombok.experimental.FieldDefaults;
 import lombok.val;
 
 @SuppressWarnings("PMD.LinguisticNaming")
-@RequiredArgsConstructor(access = PACKAGE)
-@FieldDefaults(level = PRIVATE, makeFinal = true)
-class BytesByteBuf extends BytesAbstract {
+@FieldDefaults(level = PRIVATE)
+public final class BytesByteBuf extends BytesAbstract {
 
-  static BytesByteBuf copy (@NonNull ByteBuf buffer) {
+  public static BytesByteBuf allocate (int size) {
+    val buffer = Unpooled.buffer(size);
+    buffer.clear();
+    return new BytesByteBuf(buffer);
+  }
+
+  public static BytesByteBuf wrap (@NonNull byte[] bytes) {
+    val wrapped = Unpooled.wrappedBuffer(bytes);
+    wrapped.clear();
+    return new BytesByteBuf(wrapped);
+  }
+
+  public static BytesByteBuf wrap (@NonNull ByteBuffer buffer) {
+    val wrapped = Unpooled.wrappedBuffer(buffer);
+    return new BytesByteBuf(wrapped);
+  }
+
+  public static BytesByteBuf wrap (@NonNull ByteBuf buffer) {
+    val wrapped = Unpooled.wrappedBuffer(buffer);
+    return new BytesByteBuf(wrapped);
+  }
+
+  public static BytesByteBuf copy (@NonNull byte[] bytes) {
+    val copy = Unpooled.copiedBuffer(bytes);
+    return new BytesByteBuf(copy);
+  }
+
+  public static BytesByteBuf copy (@NonNull ByteBuffer buffer) {
+    val copy = Unpooled.copiedBuffer(buffer);
+    return new BytesByteBuf(copy);
+  }
+
+  public static BytesByteBuf copy (@NonNull ByteBuf buffer) {
     val copy = buffer.copy();
     return new BytesByteBuf(copy);
   }
 
-  @NonNull
   ByteBuf buffer;
 
+  private BytesByteBuf (@NonNull ByteBuf buffer) {
+    super();
+    this.buffer = buffer;
+  }
+
   @Override
   public boolean isResizable () {
     return false;
@@ -199,6 +235,21 @@ public int capacity () {
     return buffer.capacity();
   }
 
+  @Override
+  public void capacity (int bytes) {
+    if (capacity() == bytes) {
+      return;
+    }
+
+    val oldReaderIndex = buffer.readerIndex();
+    val oldWriterIndex = buffer.writerIndex();
+    val newByteArray = Arrays.copyOf(buffer.array(), bytes);
+
+    buffer = Unpooled.wrappedBuffer(newByteArray);
+    buffer.readerIndex(Math.min(oldReaderIndex, bytes - 1));
+    buffer.writerIndex(Math.min(oldWriterIndex, bytes - 1));
+  }
+
   @Override
   public int writerIndex () {
     return buffer.writerIndex();

src/main/java/io/appulse/utils/BytesByteBuffer.java

@@ -16,34 +16,36 @@
 
 package io.appulse.utils;
 
-import static lombok.AccessLevel.PACKAGE;
 import static lombok.AccessLevel.PRIVATE;
 
 import java.nio.ByteBuffer;
 import java.nio.charset.Charset;
+import java.util.Arrays;
 
 import lombok.NonNull;
-import lombok.RequiredArgsConstructor;
 import lombok.experimental.FieldDefaults;
 import lombok.val;
 
 @FieldDefaults(level = PRIVATE)
 @SuppressWarnings("PMD.LinguisticNaming")
-@RequiredArgsConstructor(access = PACKAGE)
 class BytesByteBuffer extends BytesAbstract {
 
   static BytesByteBuffer copy (@NonNull ByteBuffer buffer) {
     val copy = buffer;
     return new BytesByteBuffer(copy);
   }
 
-  @NonNull
-  final ByteBuffer buffer;
+  ByteBuffer buffer;
 
   int writerIndex;
 
   int readerIndex;
 
+  BytesByteBuffer (@NonNull ByteBuffer buffer) {
+    super();
+    this.buffer = buffer;
+  }
+
   @Override
   public boolean isResizable () {
     return false;
@@ -244,6 +246,22 @@ public int capacity () {
     return buffer.capacity();
   }
 
+  @Override
+  public void capacity (int bytes) {
+    if (capacity() == bytes) {
+      return;
+    }
+
+    val oldPosition = buffer.position();
+    val newByteArray = Arrays.copyOf(buffer.array(), bytes);
+
+    buffer = ByteBuffer.wrap(newByteArray);
+
+    buffer.position(Math.min(oldPosition, bytes - 1));
+    writerIndex = Math.min(writerIndex, bytes - 1);
+    readerIndex = Math.min(readerIndex, bytes - 1);
+  }
+
   @Override
   public int writerIndex () {
     return writerIndex;

src/main/java/io/appulse/utils/BytesFixedArray.java

@@ -243,6 +243,16 @@ public int capacity () {
     return buffer.length;
   }
 
+  @Override
+  public void capacity (int bytes) {
+    if (capacity() == bytes) {
+      return;
+    }
+    buffer = Arrays.copyOf(buffer, bytes);
+    writerIndex = Math.min(writerIndex, bytes - 1);
+    readerIndex = Math.min(readerIndex, bytes - 1);
+  }
+
   @Override
   public int writerIndex () {
     return writerIndex;

src/test/java/io/appulse/utils/BytesTest.java

@@ -20,6 +20,8 @@
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
+import java.nio.ByteBuffer;
+
 import lombok.val;
 import org.junit.jupiter.api.Test;
 
@@ -180,4 +182,32 @@ void unsignedTest () {
     assertThat(bytes.getUnsignedInt(3))
         .isEqualTo(4_100_000_000L);
   }
+
+  @Test
+  void capacity () {
+    assertCapacity(new BytesFixedArray(2));
+    assertCapacity(new BytesByteBuffer(ByteBuffer.allocate(2)));
+    assertCapacity(BytesByteBuf.allocate(2));
+  }
+
+  private void assertCapacity (Bytes buffer) {
+    buffer.capacity(2);
+    buffer.write2B(7);
+    assertThat(buffer.capacity())
+        .isEqualTo(2);
+    assertThat(buffer.array())
+        .isEqualTo(new byte[] { 0, 7 });
+
+    buffer.capacity(4);
+    assertThat(buffer.capacity())
+        .isEqualTo(4);
+    assertThat(buffer.array())
+        .isEqualTo(new byte[] { 0, 7, 0, 0 });
+
+    buffer.capacity(1);
+    assertThat(buffer.capacity())
+        .isEqualTo(1);
+    assertThat(buffer.array())
+        .isEqualTo(new byte[] { 0 });
+  }
 }