5月8日 CMS 周二

package com.www.java;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

public class Code01 {
    //class body

    public static void main(String[] args) {
        List<String> list = new ArrayList();
        list.add("123");
        list.add("aaa");
        list.add("222");
        //list.add(333);
//      for (Object object : list) {
//          System.out.println(object);
//      }
        Iterator it = list.iterator();
        while(it.hasNext()){
            System.out.println(it.next());
        }
    }
}

package com.www.java;

public class demo01<T> {
    //class body
    public T xx;

    public T getXx() {
        return xx;
    }

    public void setXx(T xx) {
        this.xx = xx;
    }

}

package com.www.java;

public class demo02 {
    //class body
    public <T> void aa(){};
}

package com.www.java;

import java.util.ArrayList;
import java.util.List;

public class demo03 {
    //class body
    public static void main(String[] args) {
        List<String> list = new ArrayList<String>();
        list.add(new String("abc"));
        list.add(new String("def"));
//      list.add(new Integer(100));
//      list.add(new Double(1.2));
    }
}

package com.www.java;

import java.util.ArrayList;
import java.util.List;

public class demo04 {
    //class body
    private void display(List<?> list){
        System.out.println(list);
    }
    public static void main(String[] args) {
        Integer integer = new Integer(100);
        Number number = new Integer(200);
        Object object = new Integer(300);

        List<Integer> list1 = new ArrayList<Integer>();
        list1.add(integer);

        List<Number> list2 = new ArrayList<Number>();
        list2.add(number);

        List<Object> list3 = new ArrayList<Object>();
        list3.add(object);

        demo04 demo04 = new demo04();
        demo04.display(list1);
        demo04.display(list2);
        demo04.display(list3);

    }
}

package com.www.java;

import java.util.ArrayList;
import java.util.List;

public class demo05 {
    //class body
    private void display(List<? extends Number> list){
        System.out.println(list);
    }

    public static void main(String[] args) {
        Integer integer = new Integer(100);
        Number number = new Integer(200);
        Object object = new Integer(300);

        List<Integer> list1 = new ArrayList<Integer>();
        list1.add(integer);
        List<Number> list2 = new ArrayList<Number>();
        list2.add(number);
        List<Object> list3 = new ArrayList<Object>();
        list3.add(object);

        demo05 demo05 = new demo05();
        demo05.display(list1);
        demo05.display(list2);
        //demo05.display(list3);
    }
}

package com.www.java;

import java.util.ArrayList;
import java.util.List;

public class demo06 {
    //class body
    private void display(List<? super Number> list){
        System.out.println(list);
    }
    public static void main(String[] args) {
        Integer integer = new Integer(100);
        Number number = new Integer(200);
        Object object = new Integer(300);

        List<Integer> list1 = new ArrayList<Integer>();
        list1.add(integer);
        List<Number> list2 = new ArrayList<Number>();
        list2.add(number);
        List<Object> list3 = new ArrayList<Object>();
        list3.add(object);

        demo06 demo06 = new demo06();
        //demo06.display(list1);
        demo06.display(list2);
        demo06.display(list3);
    }
}

package com.www.java;

public class demo07 {
    //class body
    public <T extends Number> void method(T t){
        System.out.println(t);
    }
    public static void main(String[] args) {

        demo07 demo07 = new demo07();
        demo07.method(new Integer(100));
        demo07.method(new Double(100));
        //demo07.method(new String("abc"));

    }
}

package com.www.java;

public class demo08<T> {
    //class body
    T var;



    public demo08(T var) {
        super();
        this.var = var;
    }

    public demo08() {
        super();
    }

    public T getVar() {
        return var;
    }

    public void setVar(T var) {
        this.var = var;
    }

}

package com.www.java;

public class test01 {
    //class body
    public static void main(String[] args) {
        //1.泛型类
        //demo01<String> demo01 = new demo01<String>();

        //泛型接口
    }
}

package com.www.java;


public class test02 {
    //class body
    public static void main(String[] args) {
        demo08<String> demo08 = new demo08<String>(new String("value"));
        System.out.println(demo08.getVar());
        demo08<Integer> demo082 = new demo08<Integer>(new Integer(100));
        System.out.println(demo082.getVar());
    }
}

没死
就不要把自己当成废物
《每天一张正能量》