package org.drools.ide.debug;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.drools.ide.DroolsIDEPlugin;
import org.eclipse.debug.core.DebugException;
import org.eclipse.debug.core.model.IStackFrame;
import org.eclipse.debug.core.model.IValue;
import org.eclipse.debug.core.model.IVariable;
import org.eclipse.debug.internal.ui.views.IDebugExceptionHandler;
import org.eclipse.jface.viewers.ITreeContentProvider;
import org.eclipse.jface.viewers.Viewer;
/**
* A generic Drools debug view content provider.
*
* @author <a href="mailto:kris_verlaenen@hotmail.com">kris verlaenen </a>
*/
public class DroolsDebugViewContentProvider implements ITreeContentProvider {
private Map parentCache;
private IDebugExceptionHandler exceptionHandler;
public DroolsDebugViewContentProvider() {
parentCache = new HashMap(10);
}
public Object[] getChildren(Object parent) {
return null;
}
public Object[] getElements(Object parent) {
return getChildren(parent);
}
protected void cache(Object parent, Object[] children) {
for (int i = 0; i < children.length; i++) {
parentCache.put(children[i], parent);
}
}
public Object getParent(Object item) {
return parentCache.get(item);
}
public void dispose() {
parentCache= null;
}
protected void clearCache() {
if (parentCache != null) {
parentCache.clear();
}
}
public void removeCache(Object[] children) {
if (parentCache == null) {
return;
}
for (int i = 0; i < children.length; i++) {
parentCache.remove(children[i]);
}
}
public boolean hasChildren(Object element) {
try {
if (element instanceof IVariable) {
IValue v = ((IVariable)element).getValue();
return v != null && v.hasVariables();
}
if (element instanceof IValue) {
return ((IValue)element).hasVariables();
}
if (element instanceof IStackFrame) {
return ((IStackFrame)element).hasVariables();
}
} catch (DebugException e) {
DroolsIDEPlugin.log(e);
return false;
}
return false;
}
public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
clearCache();
}
public List getCachedDecendants(Object parent) {
Iterator children = parentCache.keySet().iterator();
List cachedChildren = new ArrayList(10);
while (children.hasNext()) {
Object child = children.next();
if (isCachedDecendant(child, parent)) {
cachedChildren.add(child);
}
}
return cachedChildren;
}
protected boolean isCachedDecendant(Object child, Object parent) {
Object p = getParent(child);
while (p != null) {
if (p.equals(parent)) {
return true;
}
p = getParent(p);
}
return false;
}
public void setExceptionHandler(IDebugExceptionHandler handler) {
exceptionHandler = handler;
}
protected IDebugExceptionHandler getExceptionHandler() {
return exceptionHandler;
}
}