【java】内存流：java.io.ByteArrayInputStream、java.io.ByteArrayOutputStream、java.io.CharArrayReader、java.io.CharArrayWriter

package 内存流;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

public class Test {
    public static void main(String[] args) throws IOException {
        String str="Hello World!中国好国国国。";
        InputStream in=new ByteArrayInputStream(str.getBytes());
        OutputStream out=new ByteArrayOutputStream();
        int tmp=0;
        while((tmp=in.read())!=-1)
            out.write(Character.toUpperCase(tmp));
        System.out.println(out);//HELLO WORLD!中冠好冠冠冠。
        //中文有乱码！！！
        in.close();
        out.close();
    }
}

package 内存流;

import java.io.CharArrayReader;
import java.io.CharArrayWriter;
import java.io.IOException;
import java.io.Reader;
import java.io.Writer;

public class Test {
    public static void main(String[] args) throws IOException {
        String str="Hello World!中国好国国国。";
        Reader in=new CharArrayReader(str.toCharArray());
        Writer out=new CharArrayWriter();
        int tmp=0;
        while((tmp=in.read())!=-1)
            out.write(Character.toUpperCase(tmp));
        System.out.println(out);//HELLO WORLD!中国好国国国。
        //字符流处理中文无乱码！！！
        in.close();
        out.close();
    }
}

package 内存流;

import java.io.*;

public class Test {
    public static void main(String[] args) throws IOException {
        File[] files={
                new File("D:"+File.separator+"testA.txt"),
                new File("D:"+File.separator+"testB.txt"),
        };
        Reader[] ins={
                    new FileReader(files[0]),
                    new FileReader(files[1])
        };
        Writer out=new CharArrayWriter();
        int tmp=0;
        while((tmp=ins[0].read())!=-1)
            out.write(tmp);
        while((tmp=ins[1].read())!=-1)
            out.write(tmp);
        System.out.println(out.toString());
//        System.out.println(new String(out.toCharArray()));
        //字节内存输出流ByteArrayOutputStream下有个类似的toByteArray()方法
        ins[0].close();
        ins[1].close();
        out.close();
    }
}