Shulou(Shulou.com)06/02 Report--

This article mainly introduces the method of easily compiling openJDK by Ubuntu. It is very detailed and has certain reference value. Friends who are interested must finish reading it.

Step 1: (follow the commands in "understanding the Java virtual machine in depth") download dependencies with one click

Sudo apt-get install build-essential gawk m4 libasound2-dev libcups2-dev libxrender-dev xorg-dev xutils-dev x11proto-print-dev binutils libmotif3 libmotif-dev ant

What is written here may not be complete, but install it for the time being. If you lack any dependency, you can follow the instructions to install it. A Buddhist programmer's day is to see the move.

The source code of openJDK has both C++ and Java, so you need a Bootstrap JDK to compile the Java part. This JDK is usually the official JDK of a version earlier than the openJDK you want to compile, according to the official README-builds (under the source root downloaded in step 2):

... The general rule is that the bootstrap JDK must be an instance of the previous major release of the JDK.

Each version of README-builds indicates the specific version of Bootstrap JDK required for this version of openJDK. For example, openJDK8 requires a version above JDK7u7, but cannot be JDK8:

Step 2: download the source code

Sudo hg clone http://hg.openjdk.java.net/jdk8u/jdk8u-dev/cd jdk8u-devchmod 755 get_source.sh./get_source.sh

Use mercurial to download the latest source code for jdk8u. If you want to download other versions of the source code, you can go here to browse: http://hg.openjdk.java.net/. The download process takes about thirty minutes.

If you don't want to use mercurial, you can also download the zip package here: http://jdk.java.net/java-se-ri/8 (at RI source code at the bottom of the page):

I compiled on windows using this zip package to extract and compile, and failed. Out of superstition, I decided to download it with mercurial on Ubuntu, and all the gods can ignore it.

Step 3: create a new setup.sh by setting the environment variable and copy the following content into it:

Replace the installation path of export LANG=C#BootStrap-JDK with the path of your bootstrap-JDK and the content to be compiled by export ALT_BOOTDIR=/usr/lib/jvm/java-7-oracle-1.7.0.80 export ALLOW_DOWNLOADS=trueexport HOTSPOT_BUILD_JOBS=8export SKIP_COMPARE_IMAGES=true#. Readers can choose the path where export BUILD_LANGTOOLS=true#export BUILD_JAXWS=false#export BUILD_JAXP=false#export BUILD_CORBA=falseexport BUILD_HOTSPOT=trueexport BUILD_JDK=trueexport SKIP_COMPARE_IMAGES=trueBUILD_DEPLOY=falseBUILD_INSTALL=false# compilation results are stored according to their needs. It is recommended to store the build folder export ALT_OUTPUTDIR=/usr/dev/jvm/openjdk/build# in the openjdk source code. These two environment variables need to be removed, otherwise there will be problems with unset JAVA_HOMEunset CLASSPATH.

Running

. / setup.sh

Just set it up again.

Step 4: compile

It takes about 20 or 30 minutes to run make in the root directory of the good openJDK source code. I was supposed to run make sanity, but I ran into this mistake again.

Mom, what the hell? after searching for a while, there was no result, so the chicken thief skipped this step and ran make directly, and it was a success. The output after success looks like this:

These are all the contents of this article entitled "Ubuntu's easy way to compile openJDK". Thank you for reading! Hope to share the content to help you, more related knowledge, welcome to follow the industry information channel!

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