IO(三)字节流练习

public class ByteStreamDemo {/*int available();                         可以取得输入文件的大小（字节个数）,没有返回0void close();                            关闭输入流abstract int read();                    读取一个字节，并把读到的字节返回,没有返回-1int read(byte[] b);                        将内容读到byte数组，并且返回读入的字节的个数。,没有返回-1int read(byte[] b ,int off ,int len);    将内容读到byte数组，从off开始读，读len个结束。,没有返回-1*//*public void close();                    关闭输出流。public void flush();                    刷新缓冲区。public void write(byte[] b);            将byte数组写入数据流write(byte[] b ,int off ,int len);        将指定范围的数据写入数据流。public abstract void write(int b);        将一个字节数据写入数据流*///输入流没有找到文件报异常，输出流没有文件会自动创建public static void executeByteFile(){File inFile = new File("D:"+File.separator+"intest.txt");File outFile = new File("D:"+File.separator+"outtest.txt");long start = System.currentTimeMillis();FileInputStream in = null;OutputStream out = null;try {in = new FileInputStream(inFile);//true表示在原文件上追加。out = new FileOutputStream(outFile,true);byte[] inb = new byte[1024];int size = 0;while ((size = in.read(inb)) != -1) {
//                System.out.println(new String(inb,0,size,"gbk"));out.write(inb, 0, size);}} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}finally{CloseUtil.close(out);CloseUtil.close(in);}System.out.println("结束时间："+(System.currentTimeMillis() - start));}/**操作字节数组的输入流* @throws IOException */public static void executeByteIn() throws IOException{final String str = "我爱中华!";byte[] bytes = str.getBytes();ByteArrayInputStream byin = new ByteArrayInputStream(bytes);byte[] db = new byte[3];int read = byin.read(db);while ( read !=-1 ) {String s = new String(db,0,read,"UTF-8");System.out.println(s);read = byin.read(db);}byin.close();}/**操作字节数组的输出流* @throws IOException */public static void executeByteOut() throws IOException{final String str1 = "我爱中华!";final String str2 = "字节数组输出流!";byte[] bytes1 = str1.getBytes();byte[] bytes2 = str2.getBytes();ByteArrayOutputStream out = new ByteArrayOutputStream();out.write(bytes1);out.write(bytes2);//先把数据都写进字节数组输出流中。之后统一输出
        System.out.println(out.toString());out.close();}/** 管道流*/public static void executePip() throws IOException{PipedByteOut out = new PipedByteOut();PipedByteIn in = new PipedByteIn();out.getOut().connect(in.getIn());Thread inThread = new Thread(in,"thread-piped-in");Thread outThread = new Thread(out,"thread-piped-out");inThread.start();outThread.start();}/** 缓存字节流*/public static void executeBufferStream() throws Exception{File inFile = new File("D:"+File.separator+"intest.txt");File outFile = new File("D:"+File.separator+"outtest.txt");long start = System.currentTimeMillis();BufferedInputStream inbuffer = new BufferedInputStream(new FileInputStream(inFile));BufferedOutputStream outbuffer = new BufferedOutputStream(new FileOutputStream(outFile,true));byte[] inb = new byte[1024];int size = 0;while ((size = inbuffer.read(inb)) != -1) {outbuffer.write(inb, 0, size);}outbuffer.flush();CloseUtil.close(outbuffer);CloseUtil.close(inbuffer);System.out.println("结束时间："+(System.currentTimeMillis() - start));}/** 对象流可以将对象序列化*/public static class SerializeUtil{public static byte[] serializeObject(Object object){ObjectOutputStream out = null;ByteArrayOutputStream by = new ByteArrayOutputStream();try {out = new ObjectOutputStream(by);out.writeObject(object);return by.toByteArray();} catch (IOException e) {throw new RuntimeException("对象序列化错误");}finally{CloseUtil.close(by);CloseUtil.close(out);}}public static <T> T unSerialized(byte[] by){if(by == null || by.length == 0) return null;ByteArrayInputStream byin = null;ObjectInputStream in = null;try {byin = new ByteArrayInputStream(by);in = new ObjectInputStream(byin);return (T) in.readObject();} catch (IOException | ClassNotFoundException e) {throw new RuntimeException("对象反序列化错误");}finally{CloseUtil.close(in);CloseUtil.close(byin);}}}public static void main(String[] args) throws Exception{User user = new User();user.setAddres("地址");user.setId(1);user.setName("测试");byte[] bs = SerializeUtil.serializeObject(user);Object object = SerializeUtil.unSerialized(bs);System.out.println(object);}
}class PipedByteIn implements Runnable{private PipedInputStream in = new PipedInputStream();@Overridepublic void run() {try {byte[] by = new byte[1024];int i = in.read(by);while (i != -1) {System.out.println(new String(by,0,i,"UTF-8"));i = in.read(by);}} catch (IOException e) {e.printStackTrace();}finally{CloseUtil.close(in);}}public PipedInputStream getIn(){return in;}
}class PipedByteOut implements Runnable{private PipedOutputStream out = new PipedOutputStream();@Overridepublic void run() {byte[] bytes = "我爱中华!".getBytes();try {out.write(bytes);} catch (IOException e) {e.printStackTrace();}finally{CloseUtil.close(out);}}public PipedOutputStream getOut(){return out;}
}class User implements Serializable{private static final long serialVersionUID = 1L;private Integer id;private String name;//transient代表该字段不被序列化private transient String addres;public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getAddres() {return addres;}public void setAddres(String addres) {this.addres = addres;}@Overridepublic String toString() {return "User [id=" + id + ", name=" + name + ", addres=" + addres + "]";}
}
class CloseUtil{public static void close(Closeable closeable){if(closeable != null){try {closeable.close();} catch (IOException e) {e.printStackTrace();}}}
}