Initial commit of OSGi Shell contribution. (FELIX-946)


git-svn-id: https://svn.apache.org/repos/asf/felix/trunk@783826 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/gogo/src/aQute/threadio/ThreadIOImpl.java b/gogo/src/aQute/threadio/ThreadIOImpl.java
new file mode 100644
index 0000000..314671a
--- /dev/null
+++ b/gogo/src/aQute/threadio/ThreadIOImpl.java
@@ -0,0 +1,78 @@
+/*
+ * 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.
+ */
+package aQute.threadio;
+
+import java.io.*;
+
+import org.osgi.service.component.*;
+import org.osgi.service.threadio.*;
+
+public class ThreadIOImpl implements ThreadIO {
+	ThreadPrintStream err = new ThreadPrintStream(System.err);
+	ThreadPrintStream out = new ThreadPrintStream(System.out);
+	ThreadInputStream in = new ThreadInputStream(System.in);
+    ThreadLocal<Marker> current = new ThreadLocal<Marker>();
+	
+	protected void activate(ComponentContext context) {
+		start();
+	}
+
+	protected void deactivate() {
+	    stop();
+	}
+	
+	public void stop() {
+		System.setErr(err.dflt);
+		System.setOut(out.dflt);
+		System.setIn(in.dflt);
+	}
+
+	public void start() {
+		if ( System.out instanceof ThreadPrintStream )
+			throw new IllegalStateException("Thread Print Stream already set");
+		System.setOut(out);
+		System.setIn(in);
+        System.setErr(err);
+	}
+	
+	public void close() {
+	    Marker top = this.current.get();
+	    if ( top == null )
+	        throw new IllegalStateException("No thread io active");
+
+	    Marker previous = top.previous;
+	    if (previous==null) {
+	        in.end();
+	        out.end();
+	        err.end();
+	    } else {
+            this.current.set(previous);
+    	    previous.activate();
+	    }
+	}
+
+	public void setStreams(InputStream in, PrintStream out, PrintStream err) {
+        assert in != null;
+        assert out != null;
+        assert err != null;
+        Marker marker = new Marker(this,in,out,err, current.get());
+	    this.current.set(marker);
+	    marker.activate();
+	}
+}