external process executor

Author: Federico Fissore

app/src/processing/app/tools/ExternalProcessExecutor.java

@@ -0,0 +1,44 @@
+package processing.app.tools;
+
+import org.apache.commons.exec.DefaultExecutor;
+import org.apache.commons.exec.ExecuteStreamHandler;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+/**
+ * Handy process executor, collecting stdout into a given OutputStream
+ */
+public class ExternalProcessExecutor extends DefaultExecutor {
+
+  public ExternalProcessExecutor(final OutputStream os) {
+    this.setStreamHandler(new ExecuteStreamHandler() {
+      @Override
+      public void setProcessInputStream(OutputStream outputStream) throws IOException {
+      }
+
+      @Override
+      public void setProcessErrorStream(InputStream inputStream) throws IOException {
+      }
+
+      @Override
+      public void setProcessOutputStream(InputStream inputStream) throws IOException {
+        byte[] buf = new byte[4096];
+        int bytes = -1;
+        while ((bytes = inputStream.read(buf)) != -1) {
+          os.write(buf, 0, bytes);
+        }
+      }
+
+      @Override
+      public void start() throws IOException {
+      }
+
+      @Override
+      public void stop() {
+      }
+    });
+
+  }
+}