/**
* Copyright 2008 Google Inc.
*
* 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.waveprotocol.wave.model.document.util;
import org.waveprotocol.wave.model.document.ReadableDocument;
/**
* Extracts the text content of subtrees in a readable document.
*
*
* @param <N>
* @param <E>
* @param <T>
*/
public class TextExtractor<N, E extends N, T extends N> {
private final ReadableDocument<N, E, T> document;
public static <N, E extends N, T extends N> String
extractInnerText(ReadableDocument<N, E, T> doc, E element) {
return new TextExtractor<N, E, T>(doc).getInnerText(element);
}
public TextExtractor(ReadableDocument<N, E, T> document) {
this.document = document;
}
public String getInnerText(E element) {
StringBuilder builder = new StringBuilder();
getInnerTextOfElement(element, builder);
return builder.toString();
}
private void getInnerTextOfNode(N node, StringBuilder builder) {
T maybeText = document.asText(node);
if (maybeText != null) {
getInnerTextOfText(maybeText, builder);
} else {
getInnerTextOfElement(document.asElement(node), builder);
}
}
private void getInnerTextOfText(T text, StringBuilder builder) {
builder.append(document.getData(text));
}
private void getInnerTextOfElement(E element, StringBuilder builder) {
N child = document.getFirstChild(element);
while (child != null) {
getInnerTextOfNode(child, builder);
child = document.getNextSibling(child);
}
}
}