First attempt Java Virtual Machine debug-start Hsdb

I am recently learning Java Virtual machine, and HSDB is the only way to learn Java virtual machine, so today tried to hsdb debugging.

First of all, I learned from Daniel Big article: Borrow Hsdb to explore the hotspot VM Runtime data, and the significance of this article is to help me as I want to learn Java virtual machine but usually too dependent on the IDE's classmates. My environment is JDK8. Nonsense not much to say, direct.

1. Create and Compile code

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Due to the usual use of eclipse, if not well equipped with path, javahome and classpath to be well first, and then cmd into the project directory, my package is hsdb, need to go into the hsdb of the superior directory, to perform the compilation:

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2.jdb Debug Code and Pause

Both Ps:jdb,jps and Sa-jdi.jar are in the JDK Lib and bin directories

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3. Use JPS to view the Java program PID

The cmd window remains fixed, reopen a new CMD window, use JPS to view the Java program's process number and perform subsequent HSDB startup operations

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In the figure we can see that the PID of main is 18392.

4. Start Hsdb

Note: Most of our Java is installed in the C:\Program files down Road This full classpath path needs to be escaped with double quotes, such as:

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After executing this command, our Hsdb tool should start. But when I started it, I reported an error: Exception in thread "Thread-1" Java.lang.UnsatisfiedLinkError:Can ' t load library:d:\program Files\java \xxx\sawindbg.dll. Refer to the following article for the resolution of HSDB, about resolving unsatisfiedlinkerror sawindbg.dll problem notes.

Then we can link to the process with the PID number.

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At this point, our HSDB tool has been connected to our Java process and can be further debugged. This article is intended to help the first time use HSDB debugging students to crawl the pit, and to make a note for themselves.

This article is from the "Instant Hua Fang" blog, please be sure to keep this source http://9903567.blog.51cto.com/9893567/1923901

First attempt Java Virtual Machine debug-start Hsdb