Apache-common项目提供的工具

---- MD5加密与生成UUID例子（依赖于commons-io.jar）：begin ----------------------------------------------------------------------------------------------------

 package com.mengyao.jdoc.commons;

 import org.apache.commons.codec.digest.DigestUtils;
 import org.apache.commons.id.Hex;
 import org.apache.commons.id.uuid.UUID;

 /**
  *
  * @author mengyao
  *
  */
 public class Utils {

     /**
      * 使用MD5单向加密方式加密指定字符串
      * @param str 待转换字符串
      * 依赖于commons-codec.jar实现
      * @return
      */
     public static String getMD5Str(String str){
         return DigestUtils.md5Hex(str);
     }

     /**
      * 获取UUID
      * 依赖于apache-commons-id.jar、commons-discovery.jar实现
      * @return
      */
     public static String getUUID() {
         return new String(Hex.encodeHex(UUID.randomUUID().getRawBytes()));
     }

     public static void main(String[] args) {
         System.out.println(getUUID());
         System.out.println(getMD5Str("123456"));
     }
 }

---- MD5加密与生成UUID例子（依赖于commons-io.jar）：end----------------------------------------------------------------------------------------------------

---- 监控文件变化例子（依赖于commons-io.jar）：begin ----------------------------------------------------------------------------------------------------

 package com.lefukj.parser.watcher;

 import java.io.File;

 import org.apache.commons.io.monitor.FileAlterationListenerAdaptor;
 import org.apache.commons.io.monitor.FileAlterationObserver;

 /**
  *
  * @author mengyao
  *
  */
 public class FileListener extends FileAlterationListenerAdaptor {  

     /**
      * 文件创建执行
      */
     @Override
     public void onFileCreate(File file) {
         System.out.println("[新建]:" + file.getAbsolutePath());
     }  

     /**
      * 文件创建修改
      */
     @Override
     public void onFileChange(File file) {
         System.out.println("[修改]:" + file.getAbsolutePath());
     }  

     /**
      * 文件删除
      */
     @Override
     public void onFileDelete(File file) {
         System.out.println("[删除]:" + file.getAbsolutePath());
     }  

     /**
      * 目录创建
      */
     @Override
     public void onDirectoryCreate(File directory) {
         System.out.println("[新建]:" + directory.getAbsolutePath());
     }  

     /**
      * 目录修改
      */
     @Override
     public void onDirectoryChange(File directory) {
         System.out.println("[修改]:" + directory.getAbsolutePath());
     }  

     /**
      * 目录删除
      */
     @Override
     public void onDirectoryDelete(File directory) {
         System.out.println("[删除]:" + directory.getAbsolutePath());
     }  

     @Override
     public void onStart(FileAlterationObserver observer) {
         super.onStart(observer);
     }  

     @Override
     public void onStop(FileAlterationObserver observer) {
         super.onStop(observer);
     }  

 } 

 package com.lefukj.parser.watcher;

 import java.util.concurrent.TimeUnit;

 import org.apache.commons.io.filefilter.FileFilterUtils;
 import org.apache.commons.io.monitor.FileAlterationMonitor;
 import org.apache.commons.io.monitor.FileAlterationObserver;

 /**
  *
  * @author mengyao
  *
  */
 public class FileMonitorTest {

     /**
      * @param args
      */
     public static void main(String[] args) throws Exception {
         // 监控目录
         String rootDir = "D:/caiji";
         // 轮询间隔1 秒
         long interval = TimeUnit.SECONDS.toMillis(1);
         // 创建一个文件观察器用于处理文件的格式
         FileAlterationObserver observer = new FileAlterationObserver(rootDir,
                 FileFilterUtils.and(FileFilterUtils.fileFileFilter(),
                         FileFilterUtils.suffixFileFilter(".dat")), // 过滤文件格式
                 null);
         // FileAlterationObserver _observer = new
         // FileAlterationObserver(rootDir);

         observer.addListener(new FileListener()); // 设置文件变化监听器
         // 创建文件变化监听器
         FileAlterationMonitor monitor = new FileAlterationMonitor(interval,
                 observer);
         // 开始监控
         monitor.start();
     }

 }

---- 监控文件变化例子（依赖于commons-io.jar）：end ----------------------------------------------------------------------------------------------------

---- 文件读写操作例子（依赖于commons-io.jar）：begin ----------------------------------------------------------------------------------------------------

 package com.lefukj.parser.utils;

 import java.io.File;
 import java.io.FileWriter;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.List;

 import org.apache.commons.io.FileUtils;
 import org.apache.commons.io.IOUtils;
 import org.apache.commons.lang.SystemUtils;

 import com.lefukj.parser.configuration.Configuration;

 /**
  *
  * @author mengyao
  *
  */
 @SuppressWarnings("all")
 public class FileUtil {

     public static String getPath(){
         String os = SystemUtils.OS_NAME;
         String path = null;
         if (os.contains("Windows") || os.contains("windows")) {
             path = Configuration.WINDOWS_FILE_DIR;
         } else if (os.contains("Linux") || os.contains("linux")) {
             path = Configuration.LINUX_FILE_DIR;
         }

         return path;
     }

     public static File getFile(String path, String fileName){
         File file = new File(path);
         if(!file.isDirectory()){
             file.mkdir();
         }
         file = new File(path+fileName);
         return file;
     }

     public static boolean writeFile(String path, String fileName, List<?> lines, boolean append) {
         boolean status = false;
         FileWriter writer = null;
         try {
             File file = new File(path);
             if(!file.isDirectory()){
                 file.mkdir();
             }
             file = new File(path+fileName);
             writer = new FileWriter(file, append);
             IOUtils.writeLines(lines, null, writer);
             status = true;
         } catch (IOException e) {
             e.printStackTrace();
             throw new RuntimeException(e);
         } finally {
             try {
                 writer.close();
             } catch (IOException e) {
                 e.printStackTrace();
             }
         }

         return status;
     }

     public static List<String> readFile(String path){
         FileUtils fileUtils = new FileUtils();
         List<String> readLines = null;
         try {
             File file = new File(path);
             readLines = fileUtils.readLines(file);
         } catch (IOException e) {
         }
         return readLines;
     }

     public static long getFileLastUpdateTime(File file){
         long lastModified = file.lastModified();

         return lastModified;
     }

     public static void main(String[] args) {
         File file = new File("D:/caiji/users.dat");
         System.out.println(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date(file.lastModified())));
         //2015-07-25 20:30:37
         //2015-07-25 20:44:01
     }

 }

---- 文件读写操作例子（依赖于commons-io.jar）：end ----------------------------------------------------------------------------------------------------