IOUtils--IO流应用

来源：互联网发布：工控软件开发是什么编辑：程序博客网时间：2024/06/10 10:54

IO字节流基类：--InputStream：--OutputStream：

IO字符流基类：--Reader：--Writer：

IO转换流：InputStreamReader 字节流通向字符流的桥梁，用于操作字节流的字符流对象。

OutputStreamWriter 字符流通向字节流的桥梁，用于操作字符流的字节流对象。

在使用IO流的时候尽量使用自定义小数组和Buffer组合，速度杠杠的！下面是自己写的一个IO工具类，自定义了异常和对IO流的处理异常（要求jdk为1.7版本以上）

public class IOUtils {
   /**
   * 用io自带缓存流拷贝数据(非文本文件！！！)
   *
   * @param address1
   *            待拷贝文件的地址
   * @param address2
   *            拷贝文件后的存放地址
   * @throws IOException
   */
   public static void copyFiles(String address1, String address2)
           throws IOException {
       // jdk1.7 提供的异常处理方法不需要手动关流
       try (BufferedInputStream bis = new BufferedInputStream(
               new FileInputStream(address1));
               BufferedOutputStream bos = new BufferedOutputStream(
                       new FileOutputStream(address2));) {
           int length;
           byte[] arr = new byte[1024 * 8];
           while ((length = bis.read(arr)) != -1) {
               bos.write(arr, 0, length);
           }
       }
   }

   /**
   * 用io自带缓存流拷贝数据(纯文本文件！！！)
   *
   * @param address1
   *            待拷贝文件的地址
   * @param address2
   *            拷贝文件后的存放地址
   * @throws IOException
   */
   public static void copyTxtFiles(String address1, String address2)
           throws IOException {
       // jdk1.7 提供的异常处理方法不需要手动关流
       try (BufferedReader br = new BufferedReader(new InputStreamReader(
               new FileInputStream(address1), "UTF-8"));
               BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(
                       new FileOutputStream(address2), "UTF-8"));) {
           int length;
           char[] arr = new char[1024 * 8];
           while ((length = br.read(arr)) != -1) {
               bw.write(arr, 0, length);
               bw.flush();// 字符流需要刷新因为中间存在一个转换的过程
           }
       }
   }

   /**
   * 将字符串转换为文件
   *
   * @param data
   * @param address
   * @throws IOException
   * @throws CustomException
   */
   public static void stringToFiles(String data, String address)
           throws IOException, CustomException {
       if (address == null || address == "") {
           throw new CustomException("文件地址为空，请检查重试！");
       }
       try (BufferedOutputStream bos = new BufferedOutputStream(
               new FileOutputStream(address));) {
           byte[] bytes = data.getBytes();
           bos.write(bytes);
       }
   }

   /**
   * 将(本地)文件转换为字符串
   *
   * @param address
   * @return
   * @throws IOException
   */
   public static String filesToString(String address) throws IOException {
       BufferedReader br = new BufferedReader(new InputStreamReader(
               new FileInputStream(address), "UTF-8"));
       StringBuffer sb = new StringBuffer();
       String msg;
       while ((msg = br.readLine()) != null) {
           sb.append(msg);
       }
       br.close();
       return sb.toString();
   }

   /**
   * 将文件转换为字符串
   *
   * @param file
   * @return
   * @throws IOException
   */
   public static String filesToString(File file) throws IOException {
       BufferedReader br = new BufferedReader(new InputStreamReader(
               new FileInputStream(file), "UTF-8"));
       StringBuffer sb = new StringBuffer();
       String msg;
       while ((msg = br.readLine()) != null) {
           sb.append(msg);
       }
       br.close();
       return sb.toString();
   }
}

/**
* 自定义异常
*
* @author Simon
*
*/
class CustomException extends Exception {

   public CustomException() {
       super();
   }

   public CustomException(String message) {
       super(message);
   }

}

0 0