Skip to content
This repository was archived by the owner on Aug 11, 2023. It is now read-only.

Added a new node class to wrap a native ROS node. #219

Merged
stonier merged 1 commit into from
Feb 25, 2016
Merged

Added a new node class to wrap a native ROS node. #219

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
103 changes: 103 additions & 0 deletions rosjava/src/main/java/org/ros/node/NativeNodeMain.java
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,103 @@
package org.ros.node;

import org.ros.node.AbstractNodeMain;
import org.ros.node.ConnectedNode;
import org.ros.node.Node;
import org.ros.namespace.GraphName;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import java.util.List;
import java.util.Map;

/**
* A java wrapper to load and run a native-code ROS node.
*
* Note: there are no actual native methods declared in this class. We only define an interface. The native methods should be declared in the child class.
*
* @author ecorbellini@creativa77.com.ar (Ernesto Corbellini)
*/
public abstract class NativeNodeMain extends AbstractNodeMain {

private Log log = LogFactory.getLog(NativeNodeMain.class);
private String libName;
private String masterUri = null;
private String hostName = null;
private String nodeName = null;
private String[] remappingArguments;
private boolean shuttingDown = false;

/**
* @param libName
* The name of the library to load.
*
* @param remappings
* A string array with ROS argument remapping pairs in each element.
**/
public NativeNodeMain(String libName, String[] remappings) {
this.libName = libName;

// if no remapping is needed, create an empty array
if (remappings == null) {
remappingArguments = new String[0];
}

log.info("Trying to load native library '" + libName + "'...");
try
{
System.loadLibrary(libName);
}
catch (SecurityException e)
{
log.info("Error loading library! SecurityException");
}
catch (UnsatisfiedLinkError e)
{
log.info("Error loading library! UnsatisfiedLinkError");
}
catch (NullPointerException e)
{
log.info("Error loading library! NullPointerException");
}
}

/**
* @param libName
* The name of the library to load.
**/
public NativeNodeMain(String libName) {
this(libName, null);
}

// These methods define the execution model interface for this node.
protected abstract void execute(String rosMasterUri, String rosHostName, String rosNodeName, String[] remappingArguments);
protected abstract void shutdown();

@Override
public void onStart(final ConnectedNode connectedNode) {
// retain important ROS info
masterUri = connectedNode.getMasterUri().toString();
hostName = connectedNode.getUri().getHost();
nodeName = this.libName;

// create a new thread to execute the native code.
new Thread() {
@Override
public void run() {
execute(masterUri, hostName, nodeName, remappingArguments);

// node execution has finished so we propagate the shutdown sequence only if we aren't already shutting down for other reasons
if(!shuttingDown) {
connectedNode.shutdown();
}
}
}.start();
}

@Override
public void onShutdown(Node node) {
shuttingDown = true;
shutdown();
}
}