Integer i = 123;
或Integer i = new Integer(123);
的{{1}}语法糖是什么?我如何证明它?给我帮忙?
答案 0 :(得分:4)
整数i = 123;整数的句法糖i = Integer.valueOf(123);
如何证明?
enter code here
首先,写一个这样的类:
public class IntegerTest {
public static void main(String[] args) {
Integer i = 123;
}
}
编译:
javac IntegerTest.java
查看生成的字节码:
javap -verbose IntegerTest
我们会得到:
public static void main(java.lang.String[]);
Code:
Stack=1, Locals=2, Args_size=1
0: bipush 123
2: invokestatic #2; //Method java/lang/Integer.valueOf:(I)Ljava/lang/Int
eger;
5: astore_1
6: return
LineNumberTable:
line 4: 0
line 5: 6
注意这一行:
invokestatic #2; //Method java/lang/Integer.valueOf:(I)Ljava/lang/Integer
调用java.lang.Integer.valueOf()方法!