| /******************************************************************************* |
| * Copyright (c) 2007 Oracle Corporation. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * Oracle - initial API and implementation |
| * |
| ********************************************************************************/ |
| package org.eclipse.jst.jsf.common.metadata.query.internal; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.StringTokenizer; |
| |
| import org.eclipse.jst.jsf.common.metadata.Entity; |
| import org.eclipse.jst.jsf.common.metadata.query.AbstractEntityQueryVisitor; |
| import org.eclipse.jst.jsf.common.metadata.query.IResultSet; |
| |
| |
| /** |
| * A simple metadata query visitor implementing {@link org.eclipse.jst.jsf.common.metadata.query.IEntityQueryVisitor} and {@link org.eclipse.jst.jsf.common.metadata.query.ITraitQueryVisitor}.<p> |
| * - simple find entity and traits by id only <br> |
| * - does not allow for wild card searchs<br> |
| * <p> |
| * TODO - fix for case-sensitivity https://bugs.eclipse.org/bugs/show_bug.cgi?id=212794 |
| * |
| */ |
| public class SimpleEntityQueryVisitorImpl extends AbstractEntityQueryVisitor implements IHierarchicalEntityVisitor { |
| private HierarchicalSearchControl control; |
| private boolean _stop; |
| |
| private EntityQueryFilterVisitor entityQuery; |
| private List<Entity> _entityResults; |
| private Entity initialEntityContext; |
| |
| /** |
| * Constructor that also creates a default SearchControl |
| */ |
| public SimpleEntityQueryVisitorImpl() { |
| super(); |
| control = new HierarchicalSearchControl(); |
| } |
| |
| /** |
| * Constructor |
| * @param control |
| */ |
| public SimpleEntityQueryVisitorImpl(final HierarchicalSearchControl control) { |
| super(); |
| this.control = control; |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.jst.jsf.common.metadata.query.IEntityQueryVisitor#findEntities(org.eclipse.jst.jsf.common.metadata.Entity, java.lang.String) |
| */ |
| public IResultSet<Entity> findEntities(final Entity initialEntity, |
| final String entityKey) { |
| |
| resetQuery(); |
| |
| if (initialEntity != null){ |
| this.initialEntityContext = initialEntity; |
| entityQuery = new EntityQueryFilterVisitor(initialEntity.getId(), entityKey); |
| initialEntity.accept(this); |
| } |
| |
| return new SimpleResultSet(getInternalEntityResults()); |
| } |
| |
| private void resetQuery() { |
| _stop = false; |
| _entityResults = null; |
| } |
| |
| private List<Entity> getInternalEntityResults(){ |
| if (_entityResults == null){ |
| _entityResults = new ArrayList<Entity>(); |
| } |
| return _entityResults; |
| } |
| |
| |
| public boolean visitEnter(final Entity entity) { |
| |
| if (entity == initialEntityContext) |
| return true; |
| |
| entityQuery.pushLevel(); |
| if (entityQuery.canVisit(entity)) |
| return entityQuery.visit(entity); |
| |
| return false; |
| } |
| |
| public boolean visitLeave(Entity entity) { |
| checkShouldStopVisitingEntities(); |
| if (entity != initialEntityContext) |
| entityQuery.popLevel(); |
| return true; |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.jst.jsf.common.metadata.query.IEntityVisitor#visit(org.eclipse.jst.jsf.common.metadata.Entity) |
| */ |
| public void visit(final Entity key) { |
| //do nothing... all work now done in visitEnter/visitLeave |
| } |
| |
| /* (non-Javadoc) |
| * @see org.eclipse.jst.jsf.common.metadata.query.IMetaDataVisitor#stopVisiting() |
| */ |
| public boolean stopVisiting() { |
| return _stop; |
| } |
| |
| private void checkShouldStopVisitingEntities(){ |
| //implement how to set stop to signal to the entity accept() to skip visiting |
| if (_stop == false |
| && control.getCountLimit()== getInternalEntityResults().size() |
| && control.getCountLimit() != SearchControl.COUNT_LIMIT_NONE ) |
| |
| _stop = true; |
| } |
| |
| /** |
| * Visitor that filters and acts upon hierarchical data that compares that an entity's id for with another with case-insensitive compare |
| */ |
| private class EntityQueryFilterVisitor { |
| |
| private String entityId; |
| private List<String> entityQueue; |
| private int curLevel = 0; |
| |
| /** |
| * Constructor |
| * @param initialContextId - Entity id from which the query is rooted |
| * @param queryKey - query key which may be compound ("A/B/C" - assuming "/" is the delimiter) |
| */ |
| public EntityQueryFilterVisitor(final String initialContextId, final String queryKey){ |
| init(initialContextId, queryKey); |
| } |
| |
| private void init(final String initialContextId, final String key) { |
| entityQueue = new ArrayList<String>(3); |
| addLevel(initialContextId); |
| if (key == null || key.trim().equals("") || key.trim().equals(getLevelDelimiter())){ //$NON-NLS-1$ |
| addLevel(""); //$NON-NLS-1$ |
| } |
| else { |
| final StringTokenizer st = new StringTokenizer(key, getLevelDelimiter()); |
| String partialKey = st.nextToken(); |
| addLevel(partialKey); |
| while (st.hasMoreElements()){ |
| partialKey = st.nextToken(); |
| addLevel(partialKey); |
| } |
| } |
| } |
| |
| /** |
| * @param entity |
| * @return flag indicating that filter was passed and children may be visited |
| */ |
| public boolean canVisit(final Entity entity) { |
| // only one filter rule... does this entity id match the current level's entity id (case-insensitive) |
| return entityId.compareTo(entity.getId().toUpperCase()) == 0; |
| } |
| |
| /** |
| * Operates on passed entity and determines if it should be part of the query results |
| * @param entity |
| * @return true if children of entity should be visited |
| */ |
| public boolean visit(final Entity entity) { |
| //one operation... if we have found the leaf-most entity in the query, add it to the results and go no deeper |
| if (curLevel == entityQueue.size() - 1) { |
| getInternalEntityResults().add(entity); |
| return false; |
| } |
| return true; |
| } |
| |
| private void addLevel(final String key) { |
| entityQueue.add(key.toUpperCase()); |
| } |
| |
| /** |
| * Move up one level in the query |
| */ |
| public void popLevel(){ |
| entityId = entityQueue.get(--curLevel); |
| } |
| |
| /** |
| * Move down one level in the query |
| */ |
| public void pushLevel() { |
| entityId = entityQueue.get(++curLevel); |
| } |
| } |
| |
| } |