package gboat2.base.bridge.util.xml;
   
   import java.io.IOException;
   import java.io.Writer;
   
   import com.sun.org.apache.xml.internal.utils.XML11Char;
   import com.sun.xml.bind.marshaller.CharacterEscapeHandler;
   
   /**
   * 对 XML 特殊字符进行转义处理的类
   * @author <a href="mailto:[email protected]">何明旺</a>
   * @since 3.0
   * @date 2014年4月1日
   */
  public class XmlCharacterEscapeHandler implements CharacterEscapeHandler {
      
      /**
       * Escape characters inside the buffer and send the output to the writer.
       * 
       * @exception IOException if something goes wrong, IOException can be thrown to stop the marshalling process.
       */
      @Override
      public void escape(char[] buf, int start, int len, boolean isAttValue, Writer out) throws IOException {
          for (int i = start; i < (start + len); i++) {
              char ch = buf[i];
  
              // you are supposed to do the standard XML character escapes like & ... &amp; < ... &lt; etc
              if (ch == '&') {
                  out.write("&amp;");
                  continue;
              }
  
              if (ch == '<') {
                  out.write("&lt;");
                  continue;
              }
  
              if (ch == '>') {
                  out.write("&gt;");
                  continue;
              }
  
              if ((ch == '"') && isAttValue) {
                  // isAttValue is set to true when the marshaller is processing attribute values.
                  // Inside attribute values, there are more things you need to escape, usually.
                  out.write("&quot;");
                  continue;
              }
  
              if ((ch == '\'') && isAttValue) {
                  out.write("&apos;");
                  continue;
              }
  
              // you should handle other characters like < or >
              if (ch > 0x7F) {
                  // escape everything above ASCII to &#xXXXX;
                  out.write("&#x");
                  out.write(Integer.toHexString(ch));
                  out.write(";");
                  continue;
              }
  
              // use apache util to check for valid xml character
              if (XML11Char.isXML11Valid(ch)) {
                  out.write(ch);
              }
          }
      }
  }