记Mac系统下JD-GUI打开，提示jdk版本需要1.8+的问题

在Mac系统下JD-GUI打开报错，提示如下

 

看报错信息提示是本地的jdk版本过低，需要升级。在终端输入"java -version"

 

 

 版本在1.8以上，应该是没问题的。然后在查下jd-gui的脚本:

#
# find installed Java versions
#################################

# first check system variable "$JAVA_HOME"
if [ -n "$JAVA_HOME" ] ; then
    JAVACMD="$JAVA_HOME/bin/java"
    
# check for specified JVMversion in "/usr/libexec/java_home" symlinks
elif [ ! -z ${JVMVersion} ] && [ -x /usr/libexec/java_home ] && /usr/libexec/java_home -F; then

    if /usr/libexec/java_home -F -v ${JVMVersion}; then
        JAVACMD="`/usr/libexec/java_home -F -v ${JVMVersion} 2> /dev/null`/bin/java"
    else
        # display error message with applescript
        osascript -e "tell application \"System Events\" to display dialog \"ERROR launching '${CFBundleName}'\n\nNo suitable Java version found on your system!\nThis program requires Java ${JVMVersion}\nMake sure you install the required Java version.\" with title \"${CFBundleName}\" buttons {\" OK \"} default button 1 with icon path to resource \"${CFBundleIconFile}\" in bundle (path to me)"
        # exit with error
        exit 3
    fi

# otherwise check "/usr/libexec/java_home" symlinks
elif [ -x /usr/libexec/java_home ] && /usr/libexec/java_home -F; then
    JAVACMD="`/usr/libexec/java_home 2> /dev/null`/bin/java"

# otherwise check Java standard symlink (old Apple Java)
elif [ -h /Library/Java/Home ]; then
    JAVACMD="/Library/Java/Home/bin/java"

# fallback: public JRE plugin (Oracle Java)
else
    JAVACMD="/Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home/bin/java"
fi

可以看到这里获取JAVACMD的过程，估计就是这里取的时候出问题了。在终端输入"echo $JAVA_HOME"，结果也是正常的1.8（程序为空估计跟zsh终端有关），但是通过执行命令"/usr/libexec/java_home"得到的是jdk17的版本。

 

 

 不知道是不是由于我的jdk安装在个人用户目录导致的，最后试了很多方法都没办法让/usr/libexec/java_home和JAVA_HOME保持一致，最后没办只能粗暴地改脚本把获取JAVACMD的逻辑都注释，强行设置为1.8的路径，问题算是半解决了。。。

#
# find installed Java versions
#################################

JAVACMD="/Users/zhugr/Library/Java/JavaVirtualMachines/adopt-openjdk-1.8.0_292/Contents/Home/bin/java"

# first check system variable "$JAVA_HOME"
# if [ -n "$JAVA_HOME" ] ; then
#     JAVACMD="$JAVA_HOME/bin/java"
    
# # check for specified JVMversion in "/usr/libexec/java_home" symlinks
# elif [ ! -z ${JVMVersion} ] && [ -x /usr/libexec/java_home ] && /usr/libexec/java_home -F; then

#     if /usr/libexec/java_home -F -v ${JVMVersion}; then
#         JAVACMD="`/usr/libexec/java_home -F -v ${JVMVersion} 2> /dev/null`/bin/java"
#     else
#         # display error message with applescript
#         osascript -e "tell application \"System Events\" to display dialog \"ERROR launching '${CFBundleName}'\n\nNo suitable Java version found on your system!\nThis program requires Java ${JVMVersion}\nMake sure you install the required Java version.\" with title \"${CFBundleName}\" buttons {\" OK \"} default button 1 with icon path to resource \"${CFBundleIconFile}\" in bundle (path to me)"
#         # exit with error
#         exit 3
#     fi

# # otherwise check "/usr/libexec/java_home" symlinks
# elif [ -x /usr/libexec/java_home ] && /usr/libexec/java_home -F; then
#     JAVACMD="`/usr/libexec/java_home 2> /dev/null`/bin/java"

# # otherwise check Java standard symlink (old Apple Java)
# elif [ -h /Library/Java/Home ]; then
#     JAVACMD="/Library/Java/Home/bin/java"

# # fallback: public JRE plugin (Oracle Java)
# else
#     JAVACMD="/Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home/bin/java"
# fi

# fallback fallback: /usr/bin/java
# but this would prompt to install deprecated Apple Java 6

先记录下来，以后涨见识了再研究下

Ps：最开始的脚本获取JAVA_HOME的时候没有获取到，而通过终端能正常输出，我猜是跟shell的命令行解析终端有关，因为脚本默认是"#!/bin/sh"，即通过sh终端解析，而mac默认的是zsh终端，所以获取的JAVA_HOME为空。然而我把"#!/bin/sh"改为"#!/bin/zsh"也没用，但是我直接把脚本拖进终端执行倒是可以正常打开，搞不懂。。。