How to configure the debugger settings. Learn more about launching, pausing and stopping a debugging session, and stepping through the program.
如下图所示,其中最重要的一个部分就是 Code 属性,Code 属性下面有行号属性 LineNumberTable,这个 LineNumberTable 就是调试器用来关联字节码和源代码的关键。关于 class 文件,可以参考: http://ginobefunny.com/post/deep_in_jvm_notes_part4/ 题外话:没有源码时如何调试? 如果没有源码,虽然在 jdb 里也可以用 s...
用IntelliJ IDEA 的调试功能可以极大提高开发效率。它具备的实时修改能力允许开发者快速迭代,迅速找到并解决问题。 “Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it.”...
IntelliJ IDEA( https://www.jetbrains.com/idea/)是我用过的最好的Java IDE工具,在研究Presto的时候,尤其是IDEA的Debug模式的功能,大大提高了我掌握Presto源码的效率,与此同时,我还用IDEA来研究Spark,Flink…
Debugging asynchronous code is a challenge because the tasks are often scheduled in one thread and executed in another. Every thread has its own stacktrace, making it difficult to figure out what happened before the thread started. IntelliJ IDEA makes it easier by establishing a connection between...
代码片段模式(Code Fragment Mode) 这两个模式类似于 Eclipse 里面的 Expression View 和 Display View。在 Display View 里也可以编写一段代码来执行,确实非常强大,但是要注意的是,这里只能写代码片段,不能自定义方法,如下图: 1.4 堆栈和线程 这个没什么好说的,一个视图可以查看当前的所有线程,另一个视图可以查...
无论你的开发工具是 IntelliJ IDEA 还是 Eclipse ,调试器都是标配。在遇到有问题的程序时,合理的利用调试器的跟踪和断点技巧,可以很快的定位出问题原因。虽然说合理利用日志也可以方便定位线上问题,但是日志并不是调试工具,不要在开发环境把System.out.println当作调试手段,掌握调试器自带的调试技能才是正道。
虽然我对 JVM 的字节码语法不熟,但有大神开发了可以在 IDEA 里查看字节码的插件:ASM Bytecode Outline,在要查看的类文件里右键选择Show bytecode Outline即可以右侧的工具栏查看我们要生成的字节码。对照着示例,我们就可以很轻松地写出操作字节码的 Java 代码了。
loadClassAndCallPremain(InstrumentationImpl.java:401) FATAL ERROR in native method: processing of -javaagent failed Disconnected from the target VM, address: '127.0.0.1:45687', transport: 'socket' Process finished with exit code 134 (inter...
(Quick note: I'm not 100% if this is the right repo for this, as I'm not 100% sure if the error is here or with the language server (or something else entirely), but trying here first) Brief backstory: My colleagues use Intellij as they ...