标准的输入输出流与转换流

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标准的输入输出流与转换流

标准的输入输出流

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import java.io.*;

/**
 * @author zss
 */
public class Test {
    public static void main(String[] args)  {
        //标准输入流，编译类型为InputStream，而运行类型为BufferInputStream
        System.out.println(System.in.getClass());

        //标准输出流，编译类型为PrintStream，运行类型为PrintStream
        System.out.println(System.out.getClass());

    }
}

image-20220703173029581

转换流

可以将字节流转换为字符流，解决文件乱码的问题，默认情况下按照utf-8编码进行阅读的

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import java.io.*;

/**
 * @author zss
 */
public class Test {
    public static void main(String[] args) throws IOException  {
        String filePath="D:\\文件下载\\hello.txt";
        BufferedReader bufferedReader=new BufferedReader(new FileReader(filePath));
        String line;
        while ((line=bufferedReader.readLine())!=null){
            System.out.println(line);
        }
        bufferedReader.close();
    }
}

image-20220703173043100

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import java.io.*;

/**
 * @author zss
 */
public class Test {
    public static void main(String[] args) throws IOException  {
        String filePath="D:\\文件下载\\hello.txt";
        //首先利用放入到InputStreamReader可以设置编码格式的构造函数，构造成这样
        InputStreamReader inputStreamReader=new InputStreamReader(new FileInputStream(filePath),"gbk");
        //然后在使用BufferedReader去重新接受
        BufferedReader bufferedReader=new BufferedReader(inputStreamReader);
        String line;
        while ((line=bufferedReader.readLine())!=null){
            System.out.println(line);
        }
        bufferedReader.close();
    }
}

image-20220703173051761

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import java.io.*;
import java.nio.charset.StandardCharsets;

/**
 * @author zss
 */
public class Test {
    public static void main(String[] args) throws IOException  {
        String filePath="D:\\文件下载\\hello.txt";
        OutputStreamWriter outputStreamWriter=new OutputStreamWriter(new FileOutputStream(filePath), StandardCharsets.UTF_8);
        BufferedWriter bufferedWriter=new BufferedWriter(outputStreamWriter);
        bufferedWriter.write("你好啊");
        bufferedWriter.close();
    }
}