javaSE-IO流 2

一、BufferedWriter的使用

1、BufferedWriterDemo

public class BufferedWriterDemo {
 
 
    public static void main(String[] args) {
        FileWriter fileWriter = null;
        BufferedWriter bufferedWriter = null;
 
        try {
            fileWriter = new FileWriter("d3.txt");
            bufferedWriter = new BufferedWriter(fileWriter);
            bufferedWriter.write(101);
            bufferedWriter.write("www.baidu.com百度".toCharArray());
            //写入一个换行
            bufferedWriter.newLine();
            bufferedWriter.write("今天天气不错！");
            bufferedWriter.flush();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                bufferedWriter.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                fileWriter.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

}

二、BufferedReader类

1、BufferedReaderDemo

public class BufferedReaderDemo {
 
    public static void main(String[] args) {
        FileReader fileReader = null;
        BufferedReader reader = null;
 
        try {
            fileReader = new FileReader("a1.txt");
            reader=  new BufferedReader(fileReader);
//            int length = 0;
//            char[] chars = new char[1024];
//            while((length = reader.read(chars))!=-1){
//                System.out.println(new String(chars,0,length));
//            }
//            String s = reader.readLine();
//            System.out.println(s);
//            s = reader.readLine();
//            System.out.println(s);
//            s = reader.readLine();
//            System.out.println(s);
//            s = reader.readLine();
//            System.out.println(s);
//            s = reader.readLine();
//            System.out.println(s);
              String str = "";
              while((str = reader.readLine())!=null){
                  System.out.println(str);
              }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                reader.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                fileReader.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

}

三、BufferedWriter的使用

1、BufferedWriterDemo

public class BufferedWriterDemo {
 
 
    public static void main(String[] args) {
        FileWriter fileWriter = null;
        BufferedWriter bufferedWriter = null;
 
        try {
            fileWriter = new FileWriter("d3.txt");
            bufferedWriter = new BufferedWriter(fileWriter);
            bufferedWriter.write(101);
            bufferedWriter.write("www.baidu.com百度".toCharArray());
            //写入一个换行
            bufferedWriter.newLine();
            bufferedWriter.write("今天天气不错！");
            bufferedWriter.flush();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                bufferedWriter.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                fileWriter.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

}

四、从万维网上摘取百度网页的操作

1、BaiduDemo

public class BaiduDemo {
 
    public static void main(String[] args) {
        BufferedReader bufferedReader = null;
        BufferedWriter bufferedWriter = null;
 
        try {
            bufferedReader = new BufferedReader(new InputStreamReader(new URL("http://www.baidu.com").openStream(),"utf-8"));
            bufferedWriter = new BufferedWriter(new FileWriter("D:\\baidu.html"));
            String str = "";
            while(( str = bufferedReader.readLine() )!=null){
                bufferedWriter.write(str);
                bufferedWriter.flush();
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                bufferedWriter.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                bufferedReader.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

}