java.5.txt

《Java就业培训教程》 作者：张孝祥 书中原代码 《Java就业培训教程》P34的Java原代码

《Java就业培训教程》P239源码
程序清单：FileTest.java
import java.io.*;
public class FileTest
{
	public static void main(String[] args)
	{
		File f=new File("c:\\1.txt");
		if(f.exists())
			f.delete();
		else
			try
			{
				f.createNewFile();
			}
			catch(Exception e)
			{
				System.out.println(e.getMessage());
			}
		System.out.println("File name:"+f.getName());
		System.out.println("File path:"+f.getPath());
		System.out.println("Abs path:"+f.getAbsolutePath());
		System.out.println("Parent:"+f.getParent());
		System.out.println(f.exists()?"exists":"does not exist");
		System.out.println(f.canWrite()?"is writeable":"is not writeable");
		System.out.println(f.canRead()?"is readable":"is not readable");
		System.out.println(f.isDirectory()?"is ":"is not"+" a directory");
		System.out.println(f.isFile()?"is normal file":"might be a named pipe");
		System.out.println(f.isAbsolute()?"is absolute":"is not absolute");
		System.out.println("File last modified:"+f.lastModified());
		System.out.println("File size:"+f.length()+" Bytes");
	}
}
《Java就业培训教程》P242源码
程序清单：RandomFileTest.java
import java.io.*;
public class RandomFileTest
{
	public static void main(String [] args) throws Exception 
	{
		Employee e1 = new Employee("zhangsan",23);
		Employee e2 = new Employee("Lisi",24);
		Employee e3 = new Employee("Wangwu",25);
		RandomAccessFile ra=new RandomAccessFile("c:\\1.txt","rw");
		ra.write(e1.name.getBytes());
		ra.writeInt(e1.age);
		ra.write(e2.name.getBytes());
		ra.writeInt(e2.age);
		ra.write(e3.name.getBytes());
		ra.writeInt(e3.age);
		ra.close();
		RandomAccessFile raf=new RandomAccessFile("c:\\1.txt","r");
		int len=8;
		raf.skipBytes(12); //跳过第一个员工的信息，其中姓名8字节，年龄4字节
		System.out.println("第二个员工信息：");
		String str="";
		for(int i=0;i<len;i++)
			str=str+(char)raf.readByte();
		System.out.println("name:"+str);
		System.out.println("age:"+raf.readInt());
		
		System.out.println("第一个员工的信息：");
		raf.seek(0); //将文件指针移动到文件开始位置
		str="";
		for(int i=0;i<len;i++)
			str=str+(char)raf.readByte();
		System.out.println("name:"+str);
		System.out.println("age:"+raf.readInt());
		
		System.out.println("第三个员工的信息：");
		raf.skipBytes(12);  //跳过第二个员工信息
		str="";
		for(int i=0;i<len;i++)
			str=str+(char)raf.readByte();
		System.out.println("name:"+str.trim());
		System.out.println("age:"+raf.readInt());
		
		raf.close();
	}
}
class Employee
{		
		String name;
		int age;
		final static int LEN=8;
		public Employee(String name,int age)
		{
			if(name.length()>LEN)
			{
				name = name.substring(0,8);
			}
			else
			{
				while(name.length()<LEN)
					name=name+"\u0000";
			}
			this.name=name;
			this.age=age;			
		}
}
《Java就业培训教程》P247源码
程序清单：FileStream.java
import java.io.*;
public class FileStream
{
	public static void main(String[] args)
	{
		File f = new File("hello.txt"); 
		try
		{
			FileOutputStream out = new FileOutputStream(f);
			byte buf[]="www.it315.org".getBytes();
			out.write(buf);
			out.close();
		}
		catch(Exception e)
		{
			System.out.println(e.getMessage());
		}
		
		try
		{
			FileInputStream in = new FileInputStream(f);
			byte [] buf = new byte[1024];
			int len = in.read(buf);
			System.out.println(new String(buf,0,len));
		}
		catch(Exception e)
		{
			System.out.println(e.getMessage());
		}
	}
}
《Java就业培训教程》P250源码
程序清单：PipeStreamTest.java
import java.io.*;
public class PipeStreamTest
{
    public static void main(String args[])
    {
        try
        {
            Sender t1=new Sender();
            Receiver t2=new Receiver();
            PipedOutputStream out = t1.getOutputStream();
            PipedInputStream in = t2.getInputStream();
            out.connect(in);
            t1.start();
            t2.start();
        }
        catch(IOException e)
        {
        	System.out.println(e.getMessage());
        }
    }
}
class Sender extends Thread
{
    private PipedOutputStream out=new PipedOutputStream();
    public PipedOutputStream getOutputStream()
    {
        return out;
    }
    public void run()
    {
        String s=new String("hello,receiver,how are you!");
        try
        {
            out.write(s.getBytes());
            out.close();
        }
        catch(IOException e)
        {
        	System.out.println(e.getMessage());
        }
    }
}
class Receiver extends Thread
{
    private PipedInputStream in=new PipedInputStream();
    public PipedInputStream getInputStream()
    {
        return in;
    }
    public void run()
    {
        String s=null;
	   byte [] buf = new byte[1024];
        try
        {
            int len =in.read(buf);
		   s = new String(buf,0,len);
            System.out.println(
"the following message comes from sender:\n"+s);
            in.close();
        }
        catch(IOException e)
        {
        	System.out.println(e.getMessage());
        }
    }
}
《Java就业培训教程》P253源码
程序清单：ByteArrayTest.java
import java.io.*;
public class ByteArrayTest
{
	public static void main(String[] args) throws Exception
	{
		String tmp="abcdefghijklmnopqrstuvwxyz";
		byte [] src =tmp.getBytes();//src为转换前的内存块
		ByteArrayInputStream input = new ByteArrayInputStream(src);
		ByteArrayOutputStream output = new ByteArrayOutputStream();
		new ByteArrayTest().transform(input,output);
		byte [] result = output.toByteArray();//result为转换后的内存块
		System.out.println(new String(result));
	}
	public void transform(InputStream in,OutputStream out)
	{
		int c=0;
		try
		{
			while((c=in.read())!=-1)//read在读到流的结尾处返回-1
			{
				int C = (int)Character.toUpperCase((char)c);
				out.write(C);
			
			}
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
	}
}
《Java就业培训教程》P263源码
程序清单：Serializatioan.java
import java.io.*;
public class serialization 
{
    public static void main(String args[]) 
throws IOException,ClassNotFoundException
    {
        Student stu=new Student(19,"dintdding",50,"huaxue");
        FileOutputStream fos=new FileOutputStream("mytext.txt");
        ObjectOutputStream os=new ObjectOutputStream(fos);
        
        try
        {
            os.writeObject(stu);
            os.close();
        }catch(IOException e)
{
	System.out.println(e.getMessage());
}
        stu=null;
        FileInputStream fi=new FileInputStream("mytext.txt");
        ObjectInputStream si=new ObjectInputStream(fi);
        try
        {
            stu=(Student)si.readObject();
            si.close();
        }catch(IOException e)
{
	System.out.println(e.getMessage());
}
        System.out.println("ID is:"+stu.id);
       System.out.println("name is:"+stu.name);
       System.out.println("age is:"+stu.age);
       System.out.println("department is:"+stu.department);
    }
    
}
class Student implements Serializable
{
    int id;
    String name;
    int age;
    String department;
    public Student(int id,String name,int age,String department)
    {
        this.id=id;
        this.name=name;
        this.age=age;
        this.department=department;
    }
}
《Java就业培训教程》P275源码
import java.io.*;
public class CharDecoder
{
	public static void main(String [] args) throws Exception
	{
		System.getProperties().put("file.encoding","iso8859-1");
		System.out.println("please enter a Chinese String");
		byte [] buf=new byte[1024];
		int ch=0;
		int pos=0;
		String strInfo=null;
		while(true)
		{            
		ch =System.in.read();
		System.out.println(Integer.toHexString(ch));
		switch(ch)
		{
			case '\r':
				break;
			case '\n':
				strInfo= new String(buf,0,pos);
				for(int i=0;i<strInfo.length();i++)
				{
					System.out.println(Integer.toHexString
						((int)strInfo.charAt(i)));
				}
				System.out.println(strInfo);
				for(int i=0;i<pos;i++)
				System.out.write(buf[i]);
				System.out.println();//想想为什么要这一句
				return;
			default:
				buf[pos++]=(byte)ch;
		}
		}			
	}
}
《Java就业培训教程》P282源码
程序清单: TestInOut.java
import java.io.*;
public class TestInOut implements Runnable
{
	Process p=null; 
	public TestInOut()
	{
        	try
		{
			p=Runtime.getRuntime().exec("java MyTest");
			new Thread(this).start();
		}
	    	catch(Exception e)
	    	{
	     		System.out.println(e.getMessage());
	    	}		
	}

	public void send()
	{
        	try
		{

        	 	OutputStream ops=p.getOutputStream(); 
         		while(true)
         		{
       				ops.write("help\r\n".getBytes());
     			}
	   	}
	    	catch(Exception e)
	    	{
	     		System.out.println(e.getMessage());
	    	}
	}
	public static void main(String [] args)
	{
		TestInOut tio=new TestInOut ();
		tio.send();

	}
	public void run()
	{
		try
		{
			InputStream in = p.getInputStream();
       			BufferedReader bfr=new BufferedReader(
       				new InputStreamReader(in));
			while(true)
			{
				String strLine=bfr.readLine();
       				System.out.println(strLine);
    			}
   		}
    		catch(Exception e)
    		{
    			System.out.println(e.getMessage());
    		}
	}
}

class MyTest
{
	public static void main(String [] args) throws IOException
	{
		while(true)
		{
			System.out.println("hi:"+
			new BufferedReader(new InputStreamReader(System.in)).readLine());
		}
	}
}