关系操作符 == != equals()

==  和!=

//: object/test.java

package object;
import java.util.*;

public class test{
    public static void main(string[] args)
    {
        integer n1 = new integer(47);
        integer n2 = new integer(47);
        system.out.println(n1 == n2);//output false
        system.out.println(n1 != n2);//output true
    }
}
//比较的是对象的引用

equals:equals 不适用于基本类型,基本类型用== !=

//: object/test.java

package object;
import java.util.*;

public class test{
    public static void main(string[] args)
    {
        int n1 = 100;
        int n2 = 100;
        system.out.println(n1==n2);//output false
    }
}

 

equals

//: object/test.java

package object;
import java.util.*;

public class test{
    public static void main(string[] args)
    {
        integer n1 = new integer(47);
        integer n2 = new integer(47);
        system.out.println(n1.equals(n2));//output true
    }
}

equals:假如自己创建自己的类 情况又不一样

//: object/test.java

package object;
import java.util.*;

class value{
    int i;
}

public class test{
    public static void main(string[] args)
    {
        value n1 = new value();
        value n2 = new value();
        n1.i = n2.i = 100;
        system.out.println(n1.equals(n2));//output false
    }
}