/*
* Copyright 2010 JBoss Inc
*
* Licensed 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 org.drools.eclipse.debug;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.drools.eclipse.DroolsEclipsePlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.debug.core.DebugException;
import org.eclipse.debug.core.DebugPlugin;
import org.eclipse.debug.core.ILogicalStructureType;
import org.eclipse.debug.core.model.IStackFrame;
import org.eclipse.debug.core.model.IValue;
import org.eclipse.debug.core.model.IVariable;
import org.eclipse.jface.viewers.ITreeContentProvider;
import org.eclipse.jface.viewers.Viewer;
/**
* A generic Drools debug view content provider.
*/
public class DroolsDebugViewContentProvider implements ITreeContentProvider {
private Map parentCache;
public DroolsDebugViewContentProvider() {
parentCache = new HashMap(10);
}
public Object[] getChildren(Object parent) {
return null;
}
public Object[] getElements(Object parent) {
Object[] result = getChildren(parent);
if (result != null && result.length == 0) {
return new Object[] { getEmptyString() };
}
return result;
}
protected String getEmptyString() {
return "Empty";
}
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) {
DroolsEclipsePlugin.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;
}
protected IValue getLogicalValue(IValue value, List previousStructureIds) {
ILogicalStructureType[] types = DebugPlugin.getLogicalStructureTypes(value);
if (types.length > 0) {
ILogicalStructureType type = DebugPlugin.getDefaultStructureType(types);
if (type != null && !previousStructureIds.contains(type.getId())) {
try {
value = type.getLogicalStructure(value);
previousStructureIds.add(type.getId());
return getLogicalValue(value, previousStructureIds);
} catch (CoreException e) {
// unable to display logical structure
}
}
}
return value;
}
}