Support stream inheritance for the forked process, fixes mojohaus#71

src/main/java/org/codehaus/mojo/exec/ExecMojo.java

@@ -131,6 +131,9 @@ public class ExecMojo
     @Parameter( property = "exec.outputFile" )
     private File outputFile;
 
+    @Parameter( property = "exec.inheritIo" )
+    private boolean inheritIo;
+
     /**
      * <p>
      * A list of arguments passed to the {@code executable}, which should be of type <code>&lt;argument&gt;</code> or
@@ -280,7 +283,7 @@ else if ( !StringUtils.isEmpty( argsProp ) )
 
             commandLine.addArguments( args, false );
 
-            Executor exec = new DefaultExecutor();
+            Executor exec = inheritIo ? new ExtendedExecutor(inheritIo) : new DefaultExecutor();
             exec.setWorkingDirectory( workingDirectory );
             fillSuccessCodes( exec );
 

src/main/java/org/codehaus/mojo/exec/ExtendedExecutor.java

@@ -0,0 +1,54 @@
+package org.codehaus.mojo.exec;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+import org.apache.commons.exec.CommandLine;
+import org.apache.commons.exec.DefaultExecutor;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.Map;
+
+/**
+ * @author Guillaume Nodet ([email protected])
+ */
+public class ExtendedExecutor extends DefaultExecutor {
+
+    private final boolean inheritIo;
+
+    public ExtendedExecutor(boolean inheritIo) {
+        this.inheritIo = inheritIo;
+    }
+
+    @Override
+    protected Process launch(CommandLine command, Map<String, String> env, File dir) throws IOException {
+        if (dir != null && !dir.exists()) {
+            throw new IOException(dir + " doesn't exist.");
+        }
+        ProcessBuilder pb = new ProcessBuilder(command.toStrings());
+        pb.environment().putAll(env);
+        pb.directory(dir);
+        if (inheritIo) {
+            pb.inheritIO();
+        }
+        return pb.start();
+    }
+
+}