/*
 * 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.xerces.util;

import org.apache.xerces.xni.XMLLocator;
import org.xml.sax.Locator;
import org.xml.sax.ext.Locator2;

/**
 * <p>A light wrapper around a SAX locator. This is useful
 * when bridging between SAX and XNI components.</p>
 * 
 * @author Michael Glavassevich, IBM
 * 
 * @version $Id$
 */
public final class SAXLocatorWrapper implements XMLLocator {
    
    private Locator fLocator = null;
    private Locator2 fLocator2 = null;
    
    public SAXLocatorWrapper() {}
    
    public void setLocator(Locator locator) {
        fLocator = locator;
        if (locator instanceof Locator2 || locator == null) {
            fLocator2 = (Locator2) locator;
        }
    }
    
    public Locator getLocator() {
        return fLocator;
    }
    
    /*
     * XMLLocator methods
     */
    
    public String getPublicId() {
        if (fLocator != null) {
            return fLocator.getPublicId();
        }
        return null;
    }
    
    public String getLiteralSystemId() {
        if (fLocator != null) {
            return fLocator.getSystemId();
        }
        return null;
    }

    public String getBaseSystemId() {
        return null;
    }

    public String getExpandedSystemId() {
        return getLiteralSystemId();
    }

    public int getLineNumber() {
        if (fLocator != null) {
            return fLocator.getLineNumber();
        }
        return -1;
    }

    public int getColumnNumber() {
        if (fLocator != null) {
            return fLocator.getColumnNumber();
        }
        return -1;
    }

    public int getCharacterOffset() {
        return -1;
    }

    public String getEncoding() {
        if (fLocator2 != null) {
            return fLocator2.getEncoding();
        }
        return null;
    }

    public String getXMLVersion() {
        if (fLocator2 != null) {
            return fLocator2.getXMLVersion();
        }
        return null;
    }
    
} // SAXLocatorWrapper
