备忘 JAVA I/O

JAVA I/O 

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.FileReader;
import java.io.IOException;

class BufferedReaderAndBufferedWriterTest {
 public static void main(String args[]) {
  try {
   FileWriter fileWriter = new FileWriter("file1.txt");
   BufferedWriter writer = new BufferedWriter(fileWriter);
   writer.write("Hello,I'am studay Java now");
   writer.newLine();
   writer.write("Please help me,Thanks!");
   System.out.println("file1.txt写入成功!-------------开始读..\n");
   writer.flush();// 刷新流,也可以不要
   writer.close();
   FileReader fileReader = new FileReader("file1.txt");
   BufferedReader reader = new BufferedReader(fileReader);
   String temp = null;
   do {
    temp = reader.readLine();
    System.out.println(temp == null ? " " : temp);
   } while (temp != null);
   reader.close();
   System.out.println("file1.txt已经读完!-----------");
  }

  catch (IOException ex) {
   ex.printStackTrace();
  }
 }
}

import java.io.*;

//练习方法

class FileDemo {
 public static void main(String args[]) {
  try {
   File file = new File("file2.txt");
   /*
    * FileWriter fileWriter = new FileWriter(file); BufferedWriter
    * writer = new BufferedWriter(fileWriter);
    * String id = "123456";
    * String name = "walt";
    * writer.write(id);
    * writer.newLine();
    * writer.write(name);
    * writer.close();
    */
   // 这个绿色地部分是写入文件,创建file2文件，改变可以显示不同地结果
   System.out.println("文件是否存在: " + file.exists());
   System.out.println("是文件吗: " + file.isFile());
   System.out.println("是文件夹吗: " + file.isDirectory());
   System.out.println("是否隐藏: " + file.isHidden());
   System.out.println("名称: " + file.getName());
   System.out.println("标准文件名: " + file.getCanonicalFile());
   System.out.println("相对路径: " + file.getPath());
   System.out.println("绝对路径: " + file.getAbsolutePath());
   System.out.println("标准路径: " + file.getCanonicalPath());
   System.out.println("最后修改时间: " + file.lastModified());
   System.out.println("文件大小: " + file.length() + " 字节");
  } catch (IOException ex) {
   ex.printStackTrace();
  }
 }
}