Java 基础一些代码练习笔记（ GenericFoo<T> 泛型2）

package com.lee2;

public class SimpleCollection<T>
{
private T[] objArr;
private int index = 0;

public SimpleCollection()
{
objArr = (T[]) new Object[10];
}

public SimpleCollection(int capacity)
{
objArr = (T[])new Object[capacity];

}

public void add(T t)
{
objArr[index++] = t;
}

public int getLength()
{
return this.index;
}

public T get(int i)     //把值取出来
{
return objArr[i];
}

public static void main(String[] args)
{
SimpleCollection<Integer> c = new SimpleCollection<Integer>();

for(int i = 0; i < 10; i++)
{
c.add(new Integer(i));
}

for(int i = 0; i < 10; i++)
{
Integer in = c.get(i);
System.out.println(in);
}
}

}

package com.lee2;public class WrapperFoo<T>{private GenericFoo3<T> foo;public GenericFoo3<T> getfoo(){return foo;}public void setFoo(GenericFoo3<T> foo){this.foo = foo;}public static void main(String[] args){GenericFoo3<Integer> foo = new GenericFoo3<Integer>();foo.setFoo(new Integer(-10));WrapperFoo<Integer> wrapper = new WrapperFoo<Integer>();wrapper.setFoo(foo);GenericFoo3<Integer> g = wrapper.getfoo();System.out.println(g.getFoo());}}class GenericFoo3<T>{private T foo;public T getFoo(){return foo;}public void setFoo(T foo){this.foo = foo;}}

package com.lee2;import java.util.ArrayList;import java.util.Iterator;import java.util.List;public class ArrayListTest{public static void main(String[] args){List<String> list = new ArrayList<String>();list.add("a");list.add("b");list.add("c");list.add("d");for(int i = 0; i < list.size(); i++){String value = list.get(i);System.out.println(value);}for(Iterator<String> iter = list.iterator(); iter.hasNext();){String value = iter.next();System.out.println(value);}}}