包装类Integer

package othertest;

import org.junit.Test;
/**
 * 
 * Integer在－128到127的范围内相等
 *
 */
public class TestInteger
{
    /**说明Integer在一定的范围内相等*/
    @Test
    public void test()
    {
        
        Integer I = 1;
        Integer J = 1;
        
        System.out.println(I == J);//返回true
        Integer K = 20003;
        Integer F = 20003;
        System.out.println(K == F);//返回false
    }
    /**测试上限范围*/
    @Test
    public void test1()
    {
        
        boolean flag = true;
        Integer I = 0;
        Integer J = 0;
        while (flag)
        {
            I++;
            J++;
            flag = (I == J);
        }
        System.out.println(I);//128
    }
    /**测试下限范围*/
    @Test
    public void test2()
    {
        boolean flag = true;
        Integer I = 0;
        Integer J = 0;
        while (flag)
        {
            I--;
            J--;
            flag = (I == J);
        }
        System.out.println(I);//-129
    }
}