Write raw javac output to a log file

Author: mensinda

plexus-compilers/plexus-compiler-javac/src/main/java/org/codehaus/plexus/compiler/javac/JavacCompiler.java

@@ -53,8 +53,13 @@
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.net.URLClassLoader;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Date;
 import java.util.List;
 import java.util.Map;
 import java.util.NoSuchElementException;
@@ -634,6 +639,14 @@ protected CompilerResult compileOutOfProcess( CompilerConfiguration config, Stri
         try
         {
             returnCode = CommandLineUtils.executeCommandLine( cli, out, out );
+            Path logsDir = config.getBuildDirectory().toPath().resolve("compiler-logs");
+            if (!Files.exists(logsDir))
+            {
+                Files.createDirectories(logsDir);
+            }
+            SimpleDateFormat dateFormat = new SimpleDateFormat("'javac'_yyyy-MM-dd_HH:mm:ss.'log'");
+            String logFileName = dateFormat.format(new Date());
+            Files.write(logsDir.resolve(logFileName), out.getOutput().getBytes(StandardCharsets.UTF_8));
 
             messages = parseModernStream( returnCode, new BufferedReader( new StringReader( out.getOutput() ) ) );
         }