IndentingWriter.java

/*
 * Copyright Red Hat Inc. and/or its affiliates and other contributors
 * as indicated by the authors tag. All rights reserved.
 *
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions
 * of the GNU General Public License version 2.
 * 
 * This particular file is subject to the "Classpath" exception as provided in the 
 * LICENSE file that accompanied this code.
 * 
 * This program is distributed in the hope that it will be useful, but WITHOUT A
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE.  See the GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License,
 * along with this distribution; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA  02110-1301, USA.
 */

package com.redhat.ceylon.tools.p2;

import javax.xml.namespace.NamespaceContext;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamWriter;

/**
 * Indenting XMLStreamWriter
 *
 * @author Stéphane Épardaud <stef@epardaud.fr>
 */
public class IndentingWriter implements XMLStreamWriter {

    private XMLStreamWriter writer;
    private int level = 0;
    private boolean first = true;

    public IndentingWriter(XMLStreamWriter writer) {
        this.writer = writer;
    }

    @Override
    public void close() throws XMLStreamException {
        writer.close();
    }

    @Override
    public void flush() throws XMLStreamException {
        writer.flush();
    }

    @Override
    public NamespaceContext getNamespaceContext() {
        return writer.getNamespaceContext();
    }

    @Override
    public String getPrefix(String uri) throws XMLStreamException {
        return writer.getPrefix(uri);
    }

    @Override
    public Object getProperty(String name) throws IllegalArgumentException {
        return writer.getProperty(name);
    }

    @Override
    public void setDefaultNamespace(String uri) throws XMLStreamException {
        writer.setDefaultNamespace(uri);
    }

    @Override
    public void setNamespaceContext(NamespaceContext context) throws XMLStreamException {
        writer.setNamespaceContext(context);
    }

    @Override
    public void setPrefix(String prefix, String uri) throws XMLStreamException {
        writer.setPrefix(prefix, uri);
    }

    @Override
    public void writeAttribute(String localName, String value) throws XMLStreamException {
        writer.writeAttribute(localName, value);
    }

    @Override
    public void writeAttribute(String namespaceURI, String localName, String value) throws XMLStreamException {
        writer.writeAttribute(namespaceURI, localName, value);
    }

    @Override
    public void writeAttribute(String prefix, String namespaceURI, String localName, String value) throws XMLStreamException {
        writer.writeAttribute(prefix, namespaceURI, localName, value);
    }

    @Override
    public void writeCData(String data) throws XMLStreamException {
        writer.writeCData(data);
    }

    @Override
    public void writeCharacters(String text) throws XMLStreamException {
        indent();
        writer.writeCharacters(text);
    }

    @Override
    public void writeCharacters(char[] text, int start, int len) throws XMLStreamException {
        indent();
        writer.writeCharacters(text, start, len);
    }

    @Override
    public void writeComment(String data) throws XMLStreamException {
        writer.writeComment(data);
    }

    @Override
    public void writeDTD(String dtd) throws XMLStreamException {
        writer.writeDTD(dtd);
    }

    @Override
    public void writeDefaultNamespace(String namespaceURI) throws XMLStreamException {
        writer.writeDefaultNamespace(namespaceURI);
    }

    @Override
    public void writeEmptyElement(String localName) throws XMLStreamException {
        indent();
        writer.writeEmptyElement(localName);
    }

    @Override
    public void writeEmptyElement(String namespaceURI, String localName) throws XMLStreamException {
        indent();
        writer.writeEmptyElement(namespaceURI, localName);
    }

    @Override
    public void writeEmptyElement(String prefix, String localName, String namespaceURI) throws XMLStreamException {
        indent();
        writer.writeEmptyElement(prefix, localName, namespaceURI);
    }

    @Override
    public void writeEndDocument() throws XMLStreamException {
        writer.writeEndDocument();
    }

    @Override
    public void writeEndElement() throws XMLStreamException {
        level--;
        indent();
        writer.writeEndElement();
    }

    @Override
    public void writeEntityRef(String name) throws XMLStreamException {
        writer.writeEntityRef(name);
    }

    @Override
    public void writeNamespace(String prefix, String namespaceURI) throws XMLStreamException {
        writer.writeNamespace(prefix, namespaceURI);
    }

    @Override
    public void writeProcessingInstruction(String target) throws XMLStreamException {
        writer.writeProcessingInstruction(target);
        newline();
    }

    @Override
    public void writeProcessingInstruction(String target, String data) throws XMLStreamException {
        writer.writeProcessingInstruction(target, data);
        newline();
    }

    @Override
    public void writeStartDocument() throws XMLStreamException {
        writer.writeStartDocument();
    }

    @Override
    public void writeStartDocument(String version) throws XMLStreamException {
        writer.writeStartDocument(version);
    }

    @Override
    public void writeStartDocument(String encoding, String version) throws XMLStreamException {
        writer.writeStartDocument(encoding, version);
        newline();
    }

    @Override
    public void writeStartElement(String localName) throws XMLStreamException {
        indent();
        writer.writeStartElement(localName);
        level++;
    }

    @Override
    public void writeStartElement(String namespaceURI, String localName) throws XMLStreamException {
        indent();
        writer.writeStartElement(namespaceURI, localName);
        level++;
    }

    @Override
    public void writeStartElement(String prefix, String localName, String namespaceURI) throws XMLStreamException {
        indent();
        writer.writeStartElement(prefix, localName, namespaceURI);
        level++;
    }

    private void newline() throws XMLStreamException{
        writer.writeCharacters("\n");
    }

    private void indent() throws XMLStreamException{
        // do not indent the root element
        if(first){
            first = false;
            return;
        }
        newline();
        for(int i=0;i<level;i++)
            writer.writeCharacters("  ");
    }
}