axiom/modules/axiom-dom/src/main/java/org/apache/axiom/om/impl/dom/CharacterImpl.java

/*
 * Copyright 2004,2005 The Apache Software Foundation.
 *
 * Licensed 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.axiom.om.impl.dom;

import org.apache.axiom.om.OMFactory;
import org.w3c.dom.CharacterData;
import org.w3c.dom.DOMException;

/**
 * This implements the OMText operations which are to be inherited by 
 * TextImpl, CommentImpl, CDATASectionImpl.
 */
public abstract class CharacterImpl extends ChildNode implements CharacterData {

	protected StringBuffer textValue;
	
	protected CharacterImpl(OMFactory factory) {
        super(factory);
	}
	
	/**
	 * @param ownerNode
	 */
	public CharacterImpl(DocumentImpl ownerNode, OMFactory factory) {
		super(ownerNode, factory);
	}

	public CharacterImpl(DocumentImpl ownerNode, String value, OMFactory factory){
		super(ownerNode, factory);
        this.textValue = (value != null) ? new StringBuffer(value)
                : new StringBuffer("");
	}
	
	///
	///org.w3c.dom.CharacterData mrthods
	///
	
	public void appendData(String value) throws DOMException {
		
		if (this.isReadonly()) {
			throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR,
					DOMMessageFormatter.formatMessage(
							DOMMessageFormatter.DOM_DOMAIN,
							"NO_MODIFICATION_ALLOWED_ERR", null));
		}
		
		this.textValue.append(value);
	}
	
	/**
	 * 
	 */
	public void deleteData(int offset, int count) throws DOMException {
		this.replaceData(offset,count,null);
	}
	
	/**
	 * If the given data is null the content will be deleted.
	 */
	public void replaceData(int offset, int count, String data) throws
                                                             DOMException {
		
		if (this.isReadonly()) {
			throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR,
					DOMMessageFormatter.formatMessage(
							DOMMessageFormatter.DOM_DOMAIN,
							"NO_MODIFICATION_ALLOWED_ERR", null));
		}
			
		int length = this.textValue.length();
		if (offset < 0 || offset > length - 1 || count < 0) {
			throw new DOMException(DOMException.INDEX_SIZE_ERR,
					DOMMessageFormatter.formatMessage(
							DOMMessageFormatter.DOM_DOMAIN, "INDEX_SIZE_ERR",
							null));
		} else {

			int end = Math.min(count + offset, length);

			if (data == null) {
				this.textValue.delete(offset, end);
			} else {
				this.textValue.replace(offset, end, data);
			}
		}

	}
	
	
	
	/**
	 * Returns the value of the data.
	 */
	public String getData() throws DOMException {
		return (this.textValue != null) ? this.textValue.toString() : "";
	}
	
	/**
	 * Inserts a string at the specified offset.
	 */
	public void insertData(int offset, String data) throws DOMException {
		int length = this.getLength();
		
		if (this.isReadonly()) {
			throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR,
					DOMMessageFormatter.formatMessage(
							DOMMessageFormatter.DOM_DOMAIN,
							"NO_MODIFICATION_ALLOWED_ERR", null));
		}
		
		if(offset < 0 || offset > length-1) {
			throw new DOMException(DOMException.INDEX_SIZE_ERR,
					DOMMessageFormatter.formatMessage(
							DOMMessageFormatter.DOM_DOMAIN,
							"INDEX_SIZE_ERR", null));
		}
		
		this.textValue.insert(offset,data);

	}

	/**
	 * Sets the text value of data.
	 */
	public void setData(String data) throws DOMException {
		if (!this.isReadonly()) {
			this.textValue.replace(0,this.getLength(), data);
		} else {
			throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR,
					DOMMessageFormatter.formatMessage(
							DOMMessageFormatter.DOM_DOMAIN,
							"NO_MODIFICATION_ALLOWED_ERR", null));
		}
	}
	
	/**
	 * Extracts a range of data from the node.
	 * @return Returns the specified substring. If the sum of offset and count 
     * exceeds the length, then all 16-bit units to the end of the data are 
     * returned.
	 */
	public String substringData(int offset, int count) throws DOMException {
		if(offset < 0 || offset > this.getLength() || count < 0) {
			throw new DOMException(DOMException.INDEX_SIZE_ERR,
					DOMMessageFormatter.formatMessage(
							DOMMessageFormatter.DOM_DOMAIN,
							"INDEX_SIZE_ERR", null));
		}
		
		int end = Math.min( count + offset, textValue.length());
		return this.textValue.substring(offset, end);
	}
	
	/**
	 * Returns the length of the string value.
	 */
	public int getLength() {
		return (this.textValue != null) ? this.textValue.length() : 0;
	}
		
}