try can use automatic resource management

Author: Vincent Potucek

compat/maven-embedder/src/main/java/org/apache/maven/cli/props/MavenProperties.java

@@ -44,6 +44,7 @@
 import java.util.Set;
 import java.util.function.UnaryOperator;
 
+import ch.qos.logback.core.Layout;
 import org.apache.maven.impl.model.DefaultInterpolator;
 
 /**
@@ -486,7 +487,9 @@ public void substitute(UnaryOperator<String> callback) {
      * @throws IOException if an error occurs
      */
     protected void saveLayout(Writer out, boolean typed) throws IOException {
-        PropertiesWriter writer = new PropertiesWriter(out, typed);
+        try(PropertiesWriter writer = new PropertiesWriter(out, typed))  {
+
+
         if (header != null) {
             for (String s : header) {
                 writer.writeln(s);
@@ -518,7 +521,7 @@ protected void saveLayout(Writer out, boolean typed) throws IOException {
                 writer.writeln(s);
             }
         }
-        writer.flush();
+        }
     }
 
     /**

impl/maven-cli/src/main/java/org/apache/maven/cling/invoker/CommonsCliOptions.java

@@ -473,9 +473,9 @@ public void displayHelp(String command, Consumer<String> pw) {
             pw.accept("");
 
             StringWriter sw = new StringWriter();
-            PrintWriter pw2 = new PrintWriter(sw);
+            try (PrintWriter writer = new PrintWriter(sw)) {
             formatter.printHelp(
-                    pw2,
+                    writer,
                     width,
                     commandLineSyntax(command),
                     System.lineSeparator() + "Options:",
@@ -484,7 +484,7 @@ public void displayHelp(String command, Consumer<String> pw) {
                     HelpFormatter.DEFAULT_DESC_PAD,
                     System.lineSeparator(),
                     false);
-            pw2.flush();
+            }
             for (String s : sw.toString().split(System.lineSeparator())) {
                 pw.accept(s);
             }

impl/maven-cli/src/main/java/org/apache/maven/cling/invoker/LookupInvoker.java

@@ -408,9 +408,9 @@ protected Consumer<String> doDetermineWriter(C context) {
             // Given the terminal creation has been offloaded to a different thread,
             // do not pass directly the terminal writer
             return msg -> {
-                PrintWriter pw = context.terminal.writer();
+                try (PrintWriter pw = context.terminal.writer()) {
                 pw.println(msg);
-                pw.flush();
+                }
             };
         }
     }

impl/maven-cli/src/main/java/org/apache/maven/cling/props/MavenProperties.java

@@ -485,7 +485,7 @@ public void substitute(UnaryOperator<String> callback) {
      * @throws IOException if an error occurs
      */
     protected void saveLayout(Writer out, boolean typed) throws IOException {
-        PropertiesWriter writer = new PropertiesWriter(out, typed);
+        try (PropertiesWriter writer = new PropertiesWriter(out, typed)) {
         if (header != null) {
             for (String s : header) {
                 writer.writeln(s);
@@ -517,7 +517,7 @@ protected void saveLayout(Writer out, boolean typed) throws IOException {
                 writer.writeln(s);
             }
         }
-        writer.flush();
+    }
     }
 
     /**

impl/maven-cli/src/main/java/org/apache/maven/cling/transfer/ConsoleMavenTransferListener.java

@@ -50,14 +50,14 @@ public ConsoleMavenTransferListener(
 
     @Override
     public void transferInitiated(TransferEvent event) {
-        overridePreviousTransfer(event);
+        overridePreviousTransfer();
 
         super.transferInitiated(event);
     }
 
     @Override
     public void transferCorrupted(TransferEvent event) throws TransferCancelledException {
-        overridePreviousTransfer(event);
+        overridePreviousTransfer();
 
         super.transferCorrupted(event);
     }
@@ -123,20 +123,20 @@ private void pad(StringBuilder buffer, int spaces) {
     @Override
     public void transferSucceeded(TransferEvent event) {
         transfers.remove(new TransferResourceIdentifier(event.getResource()));
-        overridePreviousTransfer(event);
+        overridePreviousTransfer();
 
         super.transferSucceeded(event);
     }
 
     @Override
     public void transferFailed(TransferEvent event) {
         transfers.remove(new TransferResourceIdentifier(event.getResource()));
-        overridePreviousTransfer(event);
+        overridePreviousTransfer();
 
         super.transferFailed(event);
     }
 
-    private void overridePreviousTransfer(TransferEvent event) {
+    private void overridePreviousTransfer() {
         if (lastLength > 0) {
             pad(buffer, lastLength);
             buffer.append('\r');

impl/maven-executor/src/main/java/org/apache/maven/cling/executor/forked/ForkedMavenExecutor.java

@@ -163,10 +163,8 @@ protected CountDownLatch pump(Process p, ExecutorRequest executorRequest) {
         CountDownLatch latch = new CountDownLatch(3);
         String suffix = "-pump-" + p.pid();
         Thread stdoutPump = new Thread(() -> {
-            try {
-                OutputStream stdout = executorRequest.stdOut().orElse(OutputStream.nullOutputStream());
+            try (OutputStream stdout = executorRequest.stdOut().orElse(OutputStream.nullOutputStream())){
                 p.getInputStream().transferTo(stdout);
-                stdout.flush();
             } catch (IOException e) {
                 throw new UncheckedIOException(e);
             } finally {
@@ -176,10 +174,8 @@ protected CountDownLatch pump(Process p, ExecutorRequest executorRequest) {
         stdoutPump.setName("stdout" + suffix);
         stdoutPump.start();
         Thread stderrPump = new Thread(() -> {
-            try {
-                OutputStream stderr = executorRequest.stdErr().orElse(OutputStream.nullOutputStream());
+            try (OutputStream stderr = executorRequest.stdErr().orElse(OutputStream.nullOutputStream())){
                 p.getErrorStream().transferTo(stderr);
-                stderr.flush();
             } catch (IOException e) {
                 throw new UncheckedIOException(e);
             } finally {
@@ -189,10 +185,8 @@ protected CountDownLatch pump(Process p, ExecutorRequest executorRequest) {
         stderrPump.setName("stderr" + suffix);
         stderrPump.start();
         Thread stdinPump = new Thread(() -> {
-            try {
-                OutputStream in = p.getOutputStream();
+            try (OutputStream in = p.getOutputStream()){
                 executorRequest.stdIn().orElse(InputStream.nullInputStream()).transferTo(in);
-                in.flush();
             } catch (IOException e) {
                 throw new UncheckedIOException(e);
             } finally {

its/core-it-support/core-it-plugins/maven-it-plugin-context-passing/src/main/java/org/apache/maven/plugin/coreit/CatchMojo.java

@@ -58,23 +58,10 @@ public void execute() throws MojoExecutionException {
 
         File outfile = new File(outDir, value);
 
-        Writer writer = null;
-        try {
-            writer = new FileWriter(outfile);
-
+        try (Writer writer = new FileWriter(outfile)) {
             writer.write(value);
-
-            writer.flush();
         } catch (IOException e) {
             throw new MojoExecutionException("Cannot write output file: " + outfile, e);
-        } finally {
-            if (writer != null) {
-                try {
-                    writer.close();
-                } catch (IOException e) {
-                    // ignore
-                }
-            }
         }
     }
 }

its/core-it-support/core-it-plugins/maven-it-plugin-log-file/src/main/java/org/apache/maven/plugin/coreit/AbstractLogMojo.java

@@ -78,25 +78,13 @@ protected void append(Object value) throws MojoExecutionException {
         File file = getLogFile();
         getLog().info("[MAVEN-CORE-IT-LOG] Updating log file: " + file);
         getLog().info("[MAVEN-CORE-IT-LOG]   " + value);
-        try {
-            file.getParentFile().mkdirs();
-            OutputStream out = new FileOutputStream(file, true);
-            try {
-                BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(out, encoding));
-                if (value != null) {
-                    writer.write(value.toString());
-                    writer.newLine();
-                    writer.flush();
-                }
-            } finally {
-                try {
-                    out.close();
-                } catch (IOException e) {
-                    // just ignore, we tried our best to clean up
-                }
+        if (value != null && file.getParentFile().mkdirs()) {
+            try (BufferedWriter w = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file, true), encoding))) {
+                w.write(value.toString());
+                w.newLine();
+            } catch (IOException e) {
+                throw new MojoExecutionException("Failed to update log file " + logFile, e);
             }
-        } catch (IOException e) {
-            throw new MojoExecutionException("Failed to update log file " + logFile, e);
         }
     }
 
@@ -108,19 +96,15 @@ protected void append(Object value) throws MojoExecutionException {
     protected void reset() throws MojoExecutionException {
         File file = getLogFile();
         getLog().info("[MAVEN-CORE-IT-LOG] Resetting log file: " + file);
+        if(file.getParentFile().mkdirs()){
         try {
             /*
              * NOTE: Intentionally don't delete the file but create a new empty one to check the plugin was executed.
              */
-            file.getParentFile().mkdirs();
-            OutputStream out = new FileOutputStream(file);
-            try {
-                out.close();
-            } catch (IOException e) {
-                // just ignore, we tried our best to clean up
-            }
+            new FileOutputStream(file).close();
         } catch (IOException e) {
             throw new MojoExecutionException("Failed to reset log file " + logFile, e);
         }
+        }
     }
 }