【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();
     }
 }

字节数组字节输入输出内存流

 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();
     }
 }

字符数组字符输入输出内存流

 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();
     }
 }

将多个文件读入到同一个内存输出流