jsp中sitemesh修改tagRule技术分享

/**
 * Extracts the contents of any elements that look like
 * <code><content tag="foo">...</content></code> and write the contents
 * to a page property (page.foo).
 *
 * <p>This is a cheap and cheerful mechanism for embedding multiple components in a
 * page that can be used in different places in decorators.</p>
 *
 * @author Joe Walnes
 */
public class ContentBlockExtractingRule extends BasicBlockRule<String> {
 private final ContentProperty propertyToExport;
 public ContentBlockExtractingRule(ContentProperty propertyToExport) {
  this.propertyToExport = propertyToExport;
 }
 @Override
 protected String processStart(Tag tag) throws IOException {
  tagProcessorContext.pushBuffer();
  return tag.getAttributeValue("tag", false);
 }
 @Override
 protected void processEnd(Tag tag, String tagId) throws IOException {
  propertyToExport.getChild(tagId).setValue(tagProcessorContext.currentBufferContents());
  tagProcessorContext.popBuffer();
 }
}