import java.io.FileInputStream;import java.io.FileOutputStream;/** * @author Hanlin Wang */public class FileStream { public static void main(String[] args) throws Exception { FileInputStream in = new FileInputStream("from.txt"); //准备缓冲字节数组，大小为1024个字节 byte[] buf = new byte[1024]; //开始时间 long start = System.currentTimeMillis(); //in读取字节，将读取的字节保存到buf中。len为in向buf中保存的字节数 int len = in.read(buf); //读取完成之后，释放资源 in.close(); //通过buf打印结果 System.out.PRintln(new String(buf, 0, len)); FileOutputStream out = new FileOutputStream("to.txt"); //将buf中的字节数组写入到to.txt中 out.write(buf, 0, len); //释放资源 out.close(); //结束时间 long end = System.currentTimeMillis(); //打印运行时间 System.out.println("运行时间为："+(end - start)); }}
2、BufferedInputStream&BufferedOutputStream
import java.io.BufferedInputStream;import java.io.BufferedOutputStream;import java.io.FileInputStream;import java.io.FileOutputStream;/** * @author Hanlin Wang */public class BufferedStream { public static void main(String[] args) throws Exception { BufferedInputStream in = new BufferedInputStream( new FileInputStream("from.txt")); //字节数组 byte[] buf = new byte[1024]; //开始时间 long start = System.currentTimeMillis(); //len为已读取的字节数 int len = in.read(buf); //读取完成后，释放资源 in.close(); //打印读取的数据 System.out.println(new String(buf, 0, len)); BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream("to.txt")); //写入数据到to.txt out.write(buf, 0, len); //写入完成后，释放资源 out.close(); //结束时间 long end = System.currentTimeMillis(); //打印运行时间 System.out.println("运行时间为："+(end - start)); }}
3、ByteArrayInputStream&ByteArrayOutputStream
import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.io.FileOutputStream;/** * @author Hanlin Wang */public class ByteArrayStream { public static void main(String[] args) throws Exception{ //输入流，通过构造函数注入原始数据 ByteArrayInputStream in = new ByteArrayInputStream("whataya want from me".getBytes()); //输出流，接受输入流的数据 ByteArrayOutputStream out2 = new ByteArrayOutputStream(); int len; while ((len=in.read())!=-1) { out2.write(len); } //关闭资源 in.close(); //关闭资源 out2.close(); FileOutputStream out = new FileOutputStream("to.txt"); //将out2的数据通过toByteArray()方法位字节数组，然后out写入to.txt out.write(out2.toByteArray()); //释放资源 out.close(); }}
4、DataInputStream&DataOutputStream
import java.io.BufferedInputStream;import java.io.BufferedOutputStream;import java.io.DataInputStream;import java.io.DataOutputStream;import java.io.FileInputStream;import java.io.FileOutputStream;/** * @author Hanlin Wang */public class DataStream { public static void main(String[] args) throws Exception{ //这里使用了三层装饰 FileOutputStream des = new FileOutputStream("to.txt"); BufferedOutputStream buf = new BufferedOutputStream(des); DataOutputStream out = new DataOutputStream(buf); //运用DataOutputStream的相关方法写数据 out.writeBoolean(true);//写入布尔值 out.writeByte(12);//写入字节值 out.writeUTF("您好");//写一个使用UTF-8编码的字符串 out.writeChar('1');//写入字符 out.close(); //读取to.txt的数据 FileInputStream des2 = new FileInputStream("to.txt"); BufferedInputStream buf2 = new BufferedInputStream(des2); DataInputStream in = new DataInputStream(buf2); //必须与之间写入到to.txt的顺序相同 System.out.println(in.readBoolean()); System.out.println(in.readByte()); System.out.println(in.readUTF()); System.out.println(in.readChar()); //释放资源 in.close(); }}
5、ObjectInputStream&ObjectOutputStream
import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.ObjectInputStream;import java.io.ObjectOutputStream;import java.io.Serializable;/** * @author Hanlin Wang */public class ObjectStream { public static void main(String[] args) throws Exception{ FileOutputStream out = new FileOutputStream("to.txt"); ObjectOutputStream objout = new ObjectOutputStream(out); //创建Person对象 Person p = new Person("张三", 19); //写入to.txt objout.writeObject(p); //释放资源 objout.close(); FileInputStream in = new FileInputStream("to.txt"); ObjectInputStream objin = new ObjectInputStream(in); //读取to.txt中的数据 Person p2 = (Person) objin.readObject(); System.out.println(p2.toString()); //释放资源 objin.close(); }}//定义一个Person，实现Serializable接口，保证可序列化class Person implements Serializable{ private String name; private int age; public Person(String name, int age) { this.name = name; this.age = age; } public String toString(){ return "姓名：" + name + " | 年龄：" + age; }}
6、SequenceInputStream
import java.io.ByteArrayInputStream;import java.io.FileOutputStream;import java.io.SequenceInputStream;import java.util.Enumeration;import java.util.Vector;/** * @author Hanlin Wang */public class SequenceStream { public static void main(String[] args) throws Exception{ //第一个inputstream ByteArrayInputStream in = new ByteArrayInputStream( "whataya want from me".getBytes()); //第二个inputstream ByteArrayInputStream in2 = new ByteArrayInputStream( "/nnever close our eyes".getBytes()); //释放资源（因为in、in2不做读写操作） in.close(); in2.close(); //用一个集合封装in、in2 Vector<ByteArrayInputStream> v = new Vector<ByteArrayInputStream>(); v.add(in); v.add(in2); Enumeration<ByteArrayInputStream> ele = v.elements(); //创建一个SequenceInputStream对象(SequenceInputStream ins = new SequenceInputStream(in, in2);亦可) SequenceInputStream ins = new SequenceInputStream(ele); FileOutputStream out = new FileOutputStream("to.txt"); //ins读数据，out写数据。out将ins读的数据写入to.txt中 int len; while ((len=ins.read())!=-1) { out.write(len); } //释放资源 ins.close(); out.close(); }}
import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;import java.io.PipedInputStream;import java.io.PipedOutputStream;import java.io.PrintStream;/** * @author Hanlin Wang */public class PipedStream { public static void main(String[] args) throws Exception{ final PipedInputStream in = new PipedInputStream(); final PipedOutputStream out = new PipedOutputStream(); //连接 in.connect(out); //包装out，用于向in写入数据 final PrintStream printer = new PrintStream(out); //从键盘中获取数据 final BufferedReader data = new BufferedReader( new InputStreamReader(System.in)); //reader包装in，用于获取数据 final BufferedReader reader = new BufferedReader( new InputStreamReader(in)); //创建写线程 new Thread(new Runnable() { public void run() { //将数据写入out while (true) { try { String line = data.readLine(); System.out.println(Thread.currentThread().getName() + "，发送信息："+line); System.out.println("/n发送中.../n"); Thread.sleep(5000); printer.println(line); } catch (IOException e) { e.printStackTrace(); } catch (InterruptedException e) { e.printStackTrace(); } } } }, "服务端线程").start(); //创建读线程 new Thread(new Runnable() { public void run() { while (true) { try { System.out.println(Thread.currentThread().getName()+"，收到信息："+reader.readLine()); } catch (IOException e) { e.printStackTrace(); } } } }, "客户端线程").start(); }}
8、PrintStream
import java.io.FileOutputStream;import java.io.PrintStream;/** * @author Hanlin Wang */public class PrintStream_ { public static void main(String[] args) throws Exception{ FileOutputStream out = new FileOutputStream("to.txt"); PrintStream printer = new PrintStream(out); //创建一个对象 Person p = new Person("李四", 24); //写入to.txt， printer.println(p); printer.print("Hello, it's me"); //释放资源 printer.close(); }}
字符流
1、FileReader&FileWriter
import java.io.FileReader;import java.io.FileWriter;import java.io.IOException;/** * @author Hanlin Wang */public class FileReaderAndWriter { public static void main(String[] args) throws IOException { FileReader reader = new FileReader("from.txt"); //1024大小的字符数组 char[] buf = new char[1024]; //reader读取字符，将读取的字符存入buf中。len为读取的字符数。 int len = reader.read(buf); //读取完毕后。释放资源 reader.close(); //打印读取的信息 String str = new String(buf, 0, len); System.out.println(); FileWriter writer = new FileWriter("to.txt"); //将读取的信息写入to.txt writer.write(str); //写入完成后，释放资源 writer.close(); }}
2、BufferedReader&BufferedWriter
import java.io.BufferedReader;import java.io.BufferedWriter;import java.io.FileReader;import java.io.FileWriter;/** * @author Hanlin Wang */public class BufferedReaderAndWriter { public static void main(String[] args) throws Exception{ BufferedReader test = new BufferedReader(new FileReader("from.txt")); //BufferedReader中有一个readLine方法，返回一行字符串。循环打印 String line = null; while ((line=test.readLine())!=null) { System.out.println(line); } BufferedReader reader = new BufferedReader(new FileReader("from.txt")); char[] buf = new char[1024]; //len为写入到buf的字符数 int len = reader.read(buf); //读取完成了，释放资源 reader.close(); //通过buf字符获取字符串 String str = new String(buf, 0, len); BufferedWriter writer = new BufferedWriter(new FileWriter("to.txt")); //写入数据到to.txt writer.write(str); //写入完成后，释放资源 writer.close(); }}
3、CharArrayReader&CharArrayWriter
import java.io.CharArrayReader;import java.io.CharArrayWriter;import java.io.FileWriter;/** * @author Hanlin Wang */public class CharArrayReaderAndWriter { public static void main(String[] args) throws Exception{ //输入流，通过构造函数获得原始数据 CharArrayReader reader = new CharArrayReader("u make me wanna".toCharArray()); //输出流，没有目的地，写入输入流的数据到自己本身 CharArrayWriter writer2 = new CharArrayWriter(); //writer将reader中的数据写入到自己本身，reader先读取自己的数据，复制给一个局部变量len int len; while ((len=reader.read())!=-1) { writer2.write(len); } //释放资源 reader.close(); writer2.close(); FileWriter writer = new FileWriter("to.txt"); //将writer2转换为字符数组，然后writer写入之（转换为字符串也可以） writer.write(writer2.toCharArray());//writer2.toString()亦可 //释放资源 writer.close(); }}
4、PipedReader&PipedWriter
import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;import java.io.PipedReader;import java.io.PipedWriter;import java.io.PrintWriter;/** * @author Hanlin Wang */public class PipedReaderAndWriter { public static void main(String[] args) throws Exception{ final PipedReader reader2 = new PipedReader(); final PipedWriter writer = new PipedWriter(); //连接 reader2.connect(writer); //读取键盘数据 final BufferedReader keyboard = new BufferedReader( new InputStreamReader(System.in)); //pw包装writer final PrintWriter pw = new PrintWriter(writer); //reader包装reader2，便于用readLine()方法读取pw写入的数据 final BufferedReader reader = new BufferedReader(reader2); //写数据线程 new Thread(new Runnable() { public void run() { while (true) { try { String line = keyboard.readLine(); System.out.println(Thread.currentThread().getName() + "，发送数据：" + line); System.out.println("/n发送中.../n"); Thread.sleep(3000); pw.println(line); } catch (IOException e) { e.printStackTrace(); } catch (InterruptedException e) { e.printStackTrace(); } } } }, "服务端线程").start(); //读数据线程 new Thread(new Runnable() { public void run() { while (true) { try { System.out.println(Thread.currentThread().getName() + "，收到数据："+reader.readLine()); } catch (IOException e) { e.printStackTrace(); } } } }, "客户端线程").start(); }}
5、PrintWriter
import java.io.CharArrayReader;import java.io.CharArrayWriter;import java.io.FileWriter;import java.io.PrintWriter;/** * @author Hanlin Wang */public class PrintWriter_ { public static void main(String[] args) throws Exception{ CharArrayWriter writer = new CharArrayWriter(); PrintWriter pw = new PrintWriter(writer); pw.println("hahaha"); //释放资源 pw.close(); CharArrayReader reader = new CharArrayReader(writer.toCharArray()); int len; while ((len=reader.read())!=-1) { System.out.print((char)len); } //释放资源 reader.close(); }}
6、StringReader&StringWriter
import java.io.StringReader;import java.io.StringWriter;/** * @author Hanlin Wang */public class StringReaderAndWriter { public static void main(String[] args) throws Exception{ StringWriter writer = new StringWriter(); writer.write("whataya want from me"); writer.close(); StringReader reader = new StringReader(writer.toString()); int len; while ((len=reader.read())!=-1) { System.out.print((char)len); }//System.out.println(writer.toString()); reader.close(); }}
