AbstractReader.java

/*
 * Copyright (C) 2009, 2011, 2014, 2016 XStream Committers.
 * All rights reserved.
 *
 * The software in this package is published under the terms of the BSD
 * style license a copy of which has been included with this distribution in
 * the LICENSE.txt file.
 *
 * Created on 16. August 2009 by Joerg Schaible
 */
package com.thoughtworks.xstream.io;

import java.util.Iterator;

import com.thoughtworks.xstream.core.util.Cloneables;
import com.thoughtworks.xstream.io.naming.NameCoder;
import com.thoughtworks.xstream.io.naming.NoNameCoder;


/**
 * Abstract base class for all HierarchicalStreamReader implementations. Implementations of
 * {@link HierarchicalStreamReader} should rather be derived from this class then implementing the interface directly.
 *
 * @author Jörg Schaible
 * @since 1.4
 */
public abstract class AbstractReader implements ExtendedHierarchicalStreamReader {

    private final NameCoder nameCoder;

    /**
     * Creates an AbstractReader with a NameCoder that does nothing.
     *
     * @since 1.4
     */
    protected AbstractReader() {
        this(new NoNameCoder());
    }

    /**
     * Creates an AbstractReader with a provided {@link NameCoder}.
     *
     * @param nameCoder the name coder used to read names from the incoming format
     * @since 1.4
     */
    protected AbstractReader(final NameCoder nameCoder) {
        this.nameCoder = Cloneables.cloneIfPossible(nameCoder);
    }

    @Override
    public HierarchicalStreamReader underlyingReader() {
        return this;
    }

    @Override
    public Iterator<String> getAttributeNames() {
        return new AttributeNameIterator();
    }

    /**
     * Decode a node name from the target format.
     *
     * @param name the name in the target format
     * @return the original name
     * @since 1.4
     */
    public String decodeNode(final String name) {
        return nameCoder.decodeNode(name);
    }

    /**
     * Decode an attribute name from the target format.
     *
     * @param name the name in the target format
     * @return the original name
     * @since 1.4
     */
    public String decodeAttribute(final String name) {
        return nameCoder.decodeAttribute(name);
    }

    /**
     * Encode the node name again into the name of the target format. Internally used.
     *
     * @param name the original name
     * @return the name in the target format
     * @since 1.4
     */
    protected String encodeNode(final String name) {
        return nameCoder.encodeNode(name);
    }

    /**
     * Encode the attribute name again into the name of the target format. Internally used.
     *
     * @param name the original name
     * @return the name in the target format
     * @since 1.4
     */
    protected String encodeAttribute(final String name) {
        return nameCoder.encodeAttribute(name);
    }

    @Override
    public String peekNextChild() {
        throw new UnsupportedOperationException("peekNextChild");
    }

    private class AttributeNameIterator implements Iterator<String> {

        private int current;
        private final int count;

        public AttributeNameIterator() {
            count = getAttributeCount();
        }

        @Override
        public boolean hasNext() {
            return current < count;
        }

        @Override
        public String next() {
            return getAttributeName(current++);
        }

        @Override
        public void remove() {
            throw new UnsupportedOperationException();
        }

    }
}