[問題] Integer初始化的問題
不好意思最近問題有點多...
ex1:
Integer a = 6;
bytecode:
0: bipush 6
2: invokestatic #19// Method java/lang/Integer.valueOf:(I)Ljava/lang/Integer;
5: astore_1
ex2:
Integer a = new Integer(6):
bytecode:
0: new #20 // class java/lang/Integer
3: dup
4: bipush 6
6: invokespecial #21
// Method java/lang/Integer."<init>":(I)V
9: astore_1
問題: 表面上看起來ex1好似沒有new,但實際上進到valueOf看還是new了
請問這兩個ex的差別在哪呢?
補充小問題: #數字:這個數字我查到的資料是說class裡的第幾個常量
可我不知道要怎麼利用這個變數debug... 可以舉個例子說明嗎?
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