Ant构建失败,"[javac] javac:无效目标版本:7"

Question

更新: 请在此处查看解决方案.

感谢大家的帮助!

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我在尝试使用Ant编译项目时遇到错误,它声称"[javac] javac:无效的目标版本:7"并导致构建失败.

我在Mac OSX Mavericks机器上运行javac版本1.7.0_40.Ant版本:Apache Ant(TM)版本1.8.3于2012年2月26日编译

只有在尝试使用Ant进行编译时才会出现问题.使用命令行中的javac编译项目中的单个文件(使用以下命令):

javac -d /Users/username/git/appinventor-sources/appinventor/common/build/classes/CommonUtils -classpath /Users/username/git/appinventor-sources/appinventor/common/build/classes/CommonUtils:/Users/username/git/appinventor-sources/appinventor/lib/guava/guava-14.0.1.jar -target 7 -encoding utf-8 -g:lines,vars,source -source 7 common/src/com/google/appinventor/common/utils/*

build-common.xml文件为javac指定:

<attribute name="source" default="7"/>
<attribute name="target" default="7"/>

相同的构建文件适用于其他人,可以在以下网址找到:https: //github.com/cdlockard/appinventor-sources/blob/master/appinventor/build-common.xml

看完这个,我检查了早期的Java版本我的机器上,并没有发现任何.

根据这个问题,我补充道

executable="/usr/bin/javac"

到build-common.xml文件以确保它找到了正确的Java编译器,但错误仍在继续.

命令行输出如下:

init:

CommonUtils:
[javac] Compiling 1 source file to /Users/username/git/appinventor-sources/appinventor/common/build/classes/CommonUtils
[javac] javac: invalid target release: 7
[javac] Usage: javac <options> <source files>
[javac] use -help for a list of possible options

BUILD FAILED
/Users/username/git/appinventor-sources/appinventor/build.xml:16: The following error occurred while executing this line:
/Users/username/git/appinventor-sources/appinventor/build-common.xml:318: The following error occurred while executing this line:
/Users/username/git/appinventor-sources/appinventor/common/build.xml:42: The following error occurred while executing this line:
/Users/username/git/appinventor-sources/appinventor/build-common.xml:120: Compile failed; see the compiler error output for details.

以详细方式运行ant产生了以下细节:

[javac] Compiling 1 source file to /Users/username/git/appinventor-sources/appinventor/common/build/classes/CommonUtils
[javac] Using modern compiler
[javac] Compilation arguments:
[javac] '-d'
[javac] '/Users/username/git/appinventor-sources/appinventor/common/build/classes/CommonUtils'
[javac] '-classpath'
[javac] '/Users/username/git/appinventor-sources/appinventor/common/build/classes/CommonUtils:/Users/username/git/appinventor-sources/appinventor/lib/guava/guava-14.0.1.jar'
[javac] '-target'
[javac] '7'
[javac] '-encoding'
[javac] 'utf-8'
[javac] '-g:lines,vars,source'
[javac] '-verbose'
[javac] '-source'
[javac] '7'
[javac] 
[javac] The ' characters around the executable and arguments are
[javac] not part of the command.
[javac] File to be compiled:
[javac]     /Users/username/git/appinventor-sources/appinventor/common/src/com/google/appinventor/common/utils/package-info.java
[javac] javac: invalid target release: 7
[javac] Usage: javac <options> <source files>
[javac] use -help for a list of possible options
  [ant] Exiting /Users/username/git/appinventor-sources/appinventor/common/build.xml.

有任何想法吗？非常感谢帮助.

Answer 1

问题是Ant正在我的计算机上查看Java 1.6安装(我没有意识到存在),并且由于我的$ JAVA_HOME变量未设置,因此无法找到1.7安装.我通过在.bash_profile文件中添加以下行来添加$ JAVA_HOME变量:

export JAVA_HOME='/Library/Java/JavaVirtualMachines/jdk1.7.0_40.jdk/Contents/Home'

这纠正了问题,项目建成成功.

我意识到它实际上告诉了我最初在我的Ant输出顶部的Java版本,但我以前没有注意到它:

Detected Java version: 1.6 in: /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home

一些其他注释可能对有类似问题的用户有所帮助:

- 据此,如果"fork"字段设置为yes,Ant将仅使用build-common.xml文件的javac部分的"executable"字段中的值.如果未列出,fork默认为"no",因此如果不添加它并将其设置为"yes",则将忽略"executable"值.

- 在Mac上,可以通过/ usr/bin/javac访问正确的javac可执行文件.在命令行上,您可以运行

which javac

找到命令行正在执行的文件的路径,当然

javac -version

找到它的版本号.如上所述,Ant不会在命令行PATH中查看javac,而是在JAVA_HOME中查看.

感谢大家的帮助!