SCJP: java exerciese 1

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//TestCollect .java
package com.test;
 
public class TestCollect {
    private String name;
    private int age;
 
    public String getName() {
        return name;
    }
 
    public void setName(String name) {
        this.name = name;
    }
 
    public int getAge() {
        return age;
    }
 
    public void setAge(int age) {
        this.age = age;
    }
 
    @Override
    protected void finalize() throws Throwable {
        System.out.println("Object Finalize:" + this.hashCode());
        super.finalize();
    }
 
}
//TestArgs.java
package com.test;
 
import java.util.Properties;
public class TestArgs {
    public static void main(String... args) {
        char ch='1';
        //two ways:  char [] var_name; char var_name[]; different
        //char chs[]={'\u0030','\u0031'},chss;  //48,49  chs:Array, chss:char
        char[] chs={'\u0030','\u0031'},chss;  //48,49  chs:Array, chss:Array
        System.out.println((int)(ch));
        System.out.println((chs[1]));   //1
        //chss='b';    
        //System.out.println(chss);
         
        /*System.getProperties().list(System.out); //output system properties to stdout.
        System.out.println(System.getProperty("Path", "bbb"));*/
         
        /* Test System.gc();
        TestCollect tc=new TestCollect();
        tc.setAge(23);
        tc.setName("wcg");
        System.out.println(tc.getAge());
        tc=null;        //obj ref cnt is 0, wait for collect...
         
        //System.gc();
        Runtime.getRuntime().gc();
         
        System.out.println("Please enter a int:");
        Scanner scan=new Scanner(System.in);
        int i = scan.nextInt(9);  //radix:9,数制(11)9=(10)10
        System.out.println(i);
        */
        /*
        String s=args[0];
 
        System.out.println(s);
        System.out.println("Length:"+args.length);
        for(String arg:args){
            System.out.println(arg);
        }
        Say();
        */
    }
     
 
}
posted @   庚武  Views(181)  Comments(0Edit  收藏  举报
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