字符串的切换条件如何执行？ [英] How switch cases are executed for strings?

问题描述

我对switch-case语句有疑问。
这是我的代码：

I have a doubt in switch-case statement. Here is my code :

String month = "April";
switch (month.toLowerCase()) {
            case "january":
                monthNumber = 1;
                break;
            case "february":
                monthNumber = 2;
                break;
            case "march":
                monthNumber = 3;
                break;
            case "april":
                monthNumber = 4;
                break;

依此类推。

I在这种情况下有3个问题：

I have 3 questions in this context:

1）在比较月份和案例值（即案例一月）的同时，案例
二月 ..究竟是什么编译器从以下使用？
-month.equals（ case-value）吗？
-month ==个案值？

1) While comparing month with the case values i.e case "January", case "February" .. What is exactly used from the following by compiler ?? - month.equals("case-value") ? - month == case-value ?

2）并且将大小写值在内部转换为StringBuilder / StringStringBuffer或只是将其保留为String对象？

2) And are case-values internally converted to StringBuilder/StringStringBuffer or simply they remain String object ??

3）如何从字节码中得知这一点，即有没有可用的工具可以直接查看编译器生成的代码，以找出事物内部的行为？

3) How I can I know this from byte code i.e is there any tool available using which I can view directly the compiler generated code just to find out how the things behave internally?

推荐答案

3）我相信JDeveloper具有字节码调试器功能。如果不是JDeveloper，请选择我发现的以下工具：

3) I believe JDeveloper has bytecode debugger feature. If JDeveloper is not and option, check out these tools I found:

http://sourceforge.net/projects/jbcd/

http://andrei.gmxhome.de/bytecode/index.html

http://www.drgarbage.com/how-to-debug-bytecode- with-bytecode-visualizer.html

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