JAVA操作XML大全（2）原创

import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.UnsupportedEncodingException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * xml操作助手类
 * 
 * @author FiliRon
 * @see
 */
public final class XmlHelper {
 private static final Log logger = LogFactory.getLog(XmlHelper.class);

 /**
  * 获取指定编码格式的reader
  * 
  * @param xml
  * @param encoding
  * @return
  */
 public static Reader getEncodingXmlReader(byte[] xml, String encoding) {
  try {
   return new BufferedReader(new InputStreamReader(
     new ByteArrayInputStream(xml), encoding));
  } catch (UnsupportedEncodingException e) {
   logger.debug("用指定编码[" + encoding + "]转化字节流时出现异常!" + e.getMessage());
   return null;
  }
 }

 /**
  * 读取指定全路径名的文件内容，以字节流形式返回
  * 
  * @param xmlFileFullName
  * @return 异常返回null
  */
 public static byte[] loadXmlFile(String xmlFileFullName) {
  BufferedInputStream fInput = null;
  try {
   fInput = new BufferedInputStream(XmlHelper.class.getClassLoader()
     .getResourceAsStream(xmlFileFullName));
   byte[] result = new byte[fInput.available()];
   fInput.read(result);
   return result;
  } catch (IOException e) {
   logger.debug("读取指定文件发生异常!" + e.getMessage());
   return null;
  } finally {
   try {
    if (fInput != null) {
     fInput.close();
    }
   } catch (IOException e) {
    logger.debug("关闭BufferedInputStream时发生异常!" + e.getMessage());
   }
  }
 }

 /**
  * 转化字节流的编码
  * 
  * @param srcByte
  * @param encoding
  * @return 异常返回null
  */
 public static byte[] changeEncoding(byte[] srcByte, String encoding) {
  if (srcByte == null || srcByte.length <= 0) {
   return null;
  }
  BufferedReader br = null;
  try {
   br = new BufferedReader(new InputStreamReader(
     new ByteArrayInputStream(srcByte), encoding));
   String line = new String();
   StringBuffer strBuf = new StringBuffer();
   while ((line = br.readLine()) != null) {
    strBuf.append(line);
   }
   return strBuf.toString().getBytes();
  } catch (Exception e) {
   logger.debug("用指定编码转化字节流时发生异常!" + e.getMessage());
   return null;
  } finally {
   if (br != null) {
    try {
     br.close();
    } catch (IOException e) {
     logger.debug("关闭BufferedReader时发生异常!" + e.getMessage());
    }
   }

  }

 }
}

下面是单元测试:

import junit.framework.TestCase;

public class XmlHelperTest extends TestCase {
 public void testLoadXmlFile() {
  // 该文件使用UTF-8格式保存
  String fileName = "cn/com/jdlssoft/daup/app/testfiles/xmlhelptest.txt";
  byte[] fileContents = XmlHelper.loadXmlFile(fileName);
  // 缺省字符集读出应该有问题
  assertFalse("进行xmlhelp的测试".equals(new String(fileContents)));
  fileContents = XmlHelper.changeEncoding(fileContents, "UTF-8");
  // 用UTF-8转化后应该没有问题
  assertEquals("进行xmlhelp的测试", new String(fileContents));

 }
}