Java核心类库-IO-字节数组流/内存流

内存流（数组流）：

　　把数据先临时存在数组中，待会再从数组中获取出来。

　　1. 字节内存流：ByteArrayInputStream/ByteArrayOutputStream

　　2. 字符内存流：CharArrayInputStream/CharArrayOutputStream

　　3. 字符串流：StringReader/StringWriter（把数据存放在数组中）

字节内存流：

public class ByteArrayDemo {
    public static void main(java.lang.String[] args) throws Exception {
        //字节数组输出流：程序到内存
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        bos.write("ABCD".getBytes());
        //使用存储的临时数据
        byte[] buffer = bos.toByteArray();

        //字节数组输入流：内存到程序
        ByteArrayInputStream bis = new ByteArrayInputStream(buffer);
        byte[] bys = new byte[1024];
        int len = -1;
        while ((len = bis.read(bys)) != -1) {
            System.out.print(new java.lang.String(bys,0,len));
        }
        bos.close();
        bis.close();
    }
}

字符数组流：与字节操作大致相同。

字符串流：

 1 public class StringWriterReaderDemo {
 2     public static void main(String[] args) throws IOException {
 3         //字符串的输出流
 4         StringWriter stringWriter = new StringWriter();
 5         stringWriter.write("你多大了？");
 6         stringWriter.write("21岁！");
 7
 8         //字符串的输入流
 9         StringReader stringReader = new StringReader(stringWriter.toString());
10         char[] buffer = new char[1024];
11         int len = -1;
12         while((len = stringReader.read(buffer)) != -1){
13             System.out.println(new String(buffer,0,len));
14         }
15     }
16 }