/*
* 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 org.apache.jackrabbit.core.version;
import javax.jcr.RepositoryException;
import org.apache.jackrabbit.spi.Name;
/**
* This Class implements a version selector that selects a version by label.
*
* <pre>
* V1.0
* V1.1 - "foo"
*
* new LabelVersionSelector("foo").select() --> V1.1
* new LabelVersionSelector("bar").select() --> null
*
* </pre>
*/
public class LabelVersionSelector implements VersionSelector {
/**
* a versionlabel hint
*/
private Name label = null;
/**
* Creates a <code>LabelVersionSelector</code> that will try to select a
* version with the given label.
*
* @param label label hint
*/
public LabelVersionSelector(Name label) {
this.label = label;
}
/**
* Returns the label hint
*
* @return the label hint.
*/
public Name getLabel() {
return label;
}
/**
* Sets the label hint
*
* @param label label hint
*/
public void setLabel(Name label) {
this.label = label;
}
/**
* {@inheritDoc}
*
* Selects a version from the given version history using the previously
* assigned hint in the following order: name, label, date, latest.
*/
public InternalVersion select(InternalVersionHistory versionHistory)
throws RepositoryException {
return selectByLabel(versionHistory, label);
}
/**
* Selects a version by label
*
* @param history history to select from
* @param label desired label
* @return the version with the given label or <code>null</code>
* @throws RepositoryException if an error occurs
*/
public static InternalVersion selectByLabel(InternalVersionHistory history, Name label)
throws RepositoryException {
return history.getVersionByLabel(label);
}
/**
* returns debug information
* @return debug information
*/
public String toString() {
StringBuilder ret = new StringBuilder();
ret.append("LabelVersionSelector(");
ret.append("label=");
ret.append(label);
ret.append(")");
return ret.toString();
}
}