Use unchecked exceptions instead of checked exceptions

Author: kklisura

cdtp-java-client/src/main/java/com/github/kklisura/cdtp/App.java

@@ -20,47 +20,51 @@
  * #L%
  */
 
+import static com.github.kklisura.cdtp.utils.ChromeDevToolsUtils.waitForEvent;
+
 import com.github.kklisura.cdtp.launch.ChromeLauncher;
 import com.github.kklisura.cdtp.protocol.commands.Network;
 import com.github.kklisura.cdtp.protocol.commands.Page;
 import com.github.kklisura.cdtp.services.ChromeDevToolsService;
 import com.github.kklisura.cdtp.services.ChromeService;
 import com.github.kklisura.cdtp.services.types.ChromeTab;
-import java.util.concurrent.CountDownLatch;
+import java.util.Arrays;
 
 /** Hello world! */
 public class App {
-  public static void main(String[] args) throws Exception {
+  public static void main(String[] args) throws InterruptedException {
     // Create chrome launcher
-    try (final ChromeLauncher chromeLauncher = new ChromeLauncher()) {
-
-      // Launch chrome either as headless (true) or no.
-      final ChromeService chromeService = chromeLauncher.launch(true);
+    try (final ChromeLauncher launcher = new ChromeLauncher()) {
+      // Launch chrome either as headless (true) or regular (false).
+      final ChromeService chromeService = launcher.launch(false);
 
-      // Create empty tab (about:blank)
+      // Create empty tab ie about:blank.
       final ChromeTab tab = chromeService.createTab();
 
-      // Get dev tools service to this tab
-      try (ChromeDevToolsService devToolsService = chromeService.createDevToolsService(tab)) {
+      // Get DevTools service to this tab
+      try (final ChromeDevToolsService devToolsService = chromeService.createDevToolsService(tab)) {
+        // Get individual commands
         final Network network = devToolsService.getNetwork();
         final Page page = devToolsService.getPage();
 
+        // Log requests that will be sent.
         network.onRequestWillBeSent(event -> System.out.println(event.getRequest().getUrl()));
-        network.enable();
 
-        page.navigate("http://klix.ba");
+        network.setBlockedURLs(Arrays.asList("**/*.png", "**/*.css"));
+
+        // Enable network events.
+        network.enable();
 
-        CountDownLatch countDownLatch = new CountDownLatch(1);
+        // Navigate to github.com
+        page.navigate("http://github.com");
 
-        network.onLoadingFinished(
-            event -> {
-              System.out.println("Finished");
-              countDownLatch.countDown();
-            });
+        // Wait until loading is finished.
+        waitForEvent(network::onLoadingFinished);
 
-        countDownLatch.await();
+        Thread.sleep(10000);
       }
 
+      // Close the tab.
       chromeService.closeTab(tab);
     }
   }

cdtp-java-client/src/main/java/com/github/kklisura/cdtp/launch/ChromeArguments.java

@@ -313,6 +313,7 @@ public static Builder builder() {
    *
    * @param headless Headless.
    * @return Builder. builder
+   * @throws RuntimeException If it fails to create temp directory for user-data-dir.
    */
   public static Builder defaults(boolean headless) {
     Builder builder =

cdtp-java-client/src/main/java/com/github/kklisura/cdtp/launch/ChromeLauncher.java

@@ -20,14 +20,17 @@
  * #L%
  */
 
+import static com.github.kklisura.cdtp.utils.ChromeDevToolsUtils.closeQuietly;
+
 import com.github.kklisura.cdtp.launch.config.ChromeLauncherConfiguration;
+import com.github.kklisura.cdtp.launch.exceptions.ChromeProcessException;
+import com.github.kklisura.cdtp.launch.exceptions.ChromeProcessTimeoutException;
 import com.github.kklisura.cdtp.launch.support.ProcessLauncher;
 import com.github.kklisura.cdtp.launch.support.annotations.ChromeArgument;
 import com.github.kklisura.cdtp.launch.support.impl.ProcessLauncherImpl;
 import com.github.kklisura.cdtp.services.ChromeService;
 import com.github.kklisura.cdtp.services.impl.ChromeServiceImpl;
 import java.io.BufferedReader;
-import java.io.Closeable;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.lang.reflect.Field;
@@ -40,6 +43,7 @@
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicReference;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import org.slf4j.Logger;
@@ -56,7 +60,7 @@ public class ChromeLauncher implements AutoCloseable {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(ChromeLauncher.class);
 
-  private static final Pattern DEVTOOLS_LISTENING_LINE_MATCH =
+  private static final Pattern DEVTOOLS_LISTENING_LINE_PATTERN =
       Pattern.compile("^DevTools listening on ws:\\/\\/.+?:(\\d+)\\/");
 
   private static final String[] CHROME_BINARIES =
@@ -124,10 +128,12 @@ public ChromeLauncher(
    * @param chromeBinaryPath the chrome binary path
    * @param chromeArguments the chrome arguments
    * @return Chrome service.
-   * @throws IOException the io exception
+   * @throws IllegalStateException If chrome process has already been started.
+   * @throws ChromeProcessException If an I/O error occurs during chrome process start.
+   * @throws ChromeProcessTimeoutException If timeout expired while waiting for chrome to start.
    */
   public ChromeService launch(Path chromeBinaryPath, ChromeArguments chromeArguments)
-      throws IOException {
+      throws ChromeProcessException {
     int port = launchChromeProcess(chromeBinaryPath, chromeArguments);
     return new ChromeServiceImpl(port);
   }
@@ -137,9 +143,11 @@ public ChromeService launch(Path chromeBinaryPath, ChromeArguments chromeArgumen
    *
    * @param chromeArguments the chrome arguments
    * @return Chrome service.
-   * @throws IOException the io exception
+   * @throws IllegalStateException If chrome process has already been started.
+   * @throws ChromeProcessException If an I/O error occurs during chrome process start.
+   * @throws ChromeProcessTimeoutException If timeout expired while waiting for chrome to start.
    */
-  public ChromeService launch(ChromeArguments chromeArguments) throws IOException {
+  public ChromeService launch(ChromeArguments chromeArguments) throws ChromeProcessException {
     return launch(getChromeBinaryPath(), chromeArguments);
   }
 
@@ -148,19 +156,23 @@ public ChromeService launch(ChromeArguments chromeArguments) throws IOException
    *
    * @param headless Headless flag.
    * @return Chrome service.
-   * @throws IOException the io exception
+   * @throws IllegalStateException If chrome process has already been started.
+   * @throws ChromeProcessException If an I/O error occurs during chrome process start.
+   * @throws ChromeProcessTimeoutException If timeout expired while waiting for chrome to start.
    */
-  public ChromeService launch(boolean headless) throws IOException {
+  public ChromeService launch(boolean headless) throws ChromeProcessException {
     return launch(getChromeBinaryPath(), ChromeArguments.defaults(headless).build());
   }
 
   /**
    * Launches a headless chrome with default arguments.
    *
    * @return Chrome service.
-   * @throws IOException the io exception
+   * @throws IllegalStateException If chrome process has already been started.
+   * @throws ChromeProcessException If an I/O error occurs during chrome process start.
+   * @throws ChromeProcessTimeoutException If timeout expired while waiting for chrome to start.
    */
-  public ChromeService launch() throws IOException {
+  public ChromeService launch() throws ChromeProcessException {
     return launch(true);
   }
 
@@ -177,6 +189,8 @@ public Path getChromeBinaryPath() {
       if (isExecutable) {
         return Paths.get(envChrome).toAbsolutePath();
       }
+
+      throw new RuntimeException("CHROME_PATH environment value is not an executable file.");
     }
 
     for (String binary : CHROME_BINARIES) {
@@ -220,8 +234,18 @@ public void close() {
     }
   }
 
+  /**
+   * Launches a chrome process given a chrome binary and its arguments.
+   *
+   * @param chromeBinary Chrome binary path.
+   * @param chromeArguments Chrome arguments.
+   * @return Port on which devtools is listening.
+   * @throws IllegalStateException If chrome process has already been started.
+   * @throws ChromeProcessException If an I/O error occurs during chrome process start.
+   * @throws ChromeProcessTimeoutException If timeout expired while waiting for chrome to start.
+   */
   private int launchChromeProcess(Path chromeBinary, ChromeArguments chromeArguments)
-      throws IOException {
+      throws ChromeProcessException {
     if (chromeProcess != null) {
       throw new IllegalStateException("Chrome process has already been started started.");
     }
@@ -235,34 +259,59 @@ private int launchChromeProcess(Path chromeBinary, ChromeArguments chromeArgumen
     LOGGER.info(
         "Launching chrome process {} with arguments {}", chromeBinary.toString(), argumentsMap);
 
-    chromeProcess = processLauncher.launch(chromeBinary.toString(), arguments);
-    return waitForDevToolsServer(chromeProcess);
+    try {
+      chromeProcess = processLauncher.launch(chromeBinary.toString(), arguments);
+      return waitForDevToolsServer(chromeProcess);
+    } catch (IOException e) {
+      // Unsubscribe from registry on exceptions.
+      shutdownHookRegistry.remove(shutdownHookThread);
+
+      throw new ChromeProcessException("Failed starting chrome process.", e);
+    } catch (Exception e) {
+      close();
+      throw e;
+    }
   }
 
-  private int waitForDevToolsServer(final Process process) {
+  /**
+   * Waits for DevTools server is up on chrome process.
+   *
+   * @param process Chrome process.
+   * @return DevTools listening port.
+   * @throws ChromeProcessTimeoutException If timeout expired while waiting for chrome process.
+   */
+  private int waitForDevToolsServer(final Process process) throws ChromeProcessTimeoutException {
     final AtomicInteger port = new AtomicInteger();
     final AtomicBoolean success = new AtomicBoolean(false);
+    final AtomicReference<String> chromeOutput = new AtomicReference<>("");
 
     Thread readLineThread =
         new Thread(
             () -> {
+              StringBuilder chromeOutputBuilder = new StringBuilder();
               BufferedReader reader = null;
               try {
                 reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
 
                 // Wait for DevTools listening line and extract port number.
                 String line;
                 while ((line = reader.readLine()) != null) {
-                  Matcher matcher = DEVTOOLS_LISTENING_LINE_MATCH.matcher(line);
+                  Matcher matcher = DEVTOOLS_LISTENING_LINE_PATTERN.matcher(line);
                   if (matcher.find()) {
                     port.set(Integer.parseInt(matcher.group(1)));
                     success.set(true);
                     break;
                   }
+
+                  if (chromeOutputBuilder.length() != 0) {
+                    chromeOutputBuilder.append(System.lineSeparator());
+                  }
+                  chromeOutputBuilder.append(line);
                 }
               } catch (Exception e) {
                 LOGGER.error("Failed while waiting for dev tools server.", e);
               } finally {
+                chromeOutput.set(chromeOutputBuilder.toString());
                 closeQuietly(reader);
               }
             });
@@ -274,7 +323,11 @@ private int waitForDevToolsServer(final Process process) {
 
       if (!success.get()) {
         close(readLineThread);
-        throw new RuntimeException("Failed while waiting for chrome to start. Timeout expired!");
+
+        throw new ChromeProcessTimeoutException(
+            "Failed while waiting for chrome to start: "
+                + "Timeout expired! Chrome output: "
+                + chromeOutput.get());
       }
     } catch (InterruptedException e) {
       close(readLineThread);
@@ -287,7 +340,6 @@ private int waitForDevToolsServer(final Process process) {
   }
 
   private void close(Thread thread) {
-    close();
     try {
       thread.join(TimeUnit.SECONDS.toMillis(configuration.getThreadWaitTime()));
     } catch (InterruptedException e) {
@@ -332,16 +384,6 @@ private Map<String, Object> getArguments(ChromeArguments arguments) {
     return args;
   }
 
-  private static void closeQuietly(Closeable closeable) {
-    if (closeable != null) {
-      try {
-        closeable.close();
-      } catch (IOException e) {
-        // Ignore this exception.
-      }
-    }
-  }
-
   /** Environment interface. */
   @FunctionalInterface
   public interface Environment {

cdtp-java-client/src/main/java/com/github/kklisura/cdtp/launch/exceptions/ChromeProcessException.java

@@ -0,0 +1,47 @@
+package com.github.kklisura.cdtp.launch.exceptions;
+
+/*-
+ * #%L
+ * cdpt-java-client
+ * %%
+ * Copyright (C) 2018 Kenan Klisura
+ * %%
+ * 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
+ *
+ *      http://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.
+ * #L%
+ */
+
+/**
+ * Chrome process exception raised when error occurs during chrome startup.
+ *
+ * @author Kenan Klisura
+ */
+public class ChromeProcessException extends RuntimeException {
+  /**
+   * Instantiates a new Chrome process exception.
+   *
+   * @param message Message.
+   */
+  public ChromeProcessException(String message) {
+    super(message);
+  }
+
+  /**
+   * Instantiates a new Chrome process exception.
+   *
+   * @param message Message.
+   * @param cause Root exception cause.
+   */
+  public ChromeProcessException(String message, Throwable cause) {
+    super(message, cause);
+  }
+}

cdtp-java-client/src/main/java/com/github/kklisura/cdtp/launch/exceptions/ChromeProcessTimeoutException.java

@@ -0,0 +1,47 @@
+package com.github.kklisura.cdtp.launch.exceptions;
+
+/*-
+ * #%L
+ * cdpt-java-client
+ * %%
+ * Copyright (C) 2018 Kenan Klisura
+ * %%
+ * 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
+ *
+ *      http://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.
+ * #L%
+ */
+
+/**
+ * Exception thrown when timeout expired when waiting for chrome process.
+ *
+ * @author Kenan Klisura
+ */
+public class ChromeProcessTimeoutException extends ChromeProcessException {
+  /**
+   * Instantiates a new Chrome process timeout exception.
+   *
+   * @param message Message.
+   */
+  public ChromeProcessTimeoutException(String message) {
+    super(message);
+  }
+
+  /**
+   * Instantiates a new Chrome process timeout exception.
+   *
+   * @param message Message.
+   * @param cause Exception cause
+   */
+  public ChromeProcessTimeoutException(String message, Throwable cause) {
+    super(message, cause);
+  }
+}