使用`Runtime.getRuntime（）。exec`从Java启动的进程无法访问文件系统位置
进程使用Runtime.getRuntime().exec从Java启动Runtime.getRuntime().exec具有较少的权限，我在JavaDocs中没有看到相关描述以及如何管理它。
如何确保启动的进程具有相同的环境和权限？
更多细节：
为maven和gradle编写轻量级Eclipse插件。 （这个问题经过测试不会与Eclipse有关，最后会看到。）
我从Eclipse插件中启动mvn和gradle ：
对于gradle gralde build无法创建临时文件：
Eclipse插件开发 – Gradle无法从Eclipse启动器运行：java.io.IOException：拒绝访问
对于maven D:\Progs\springsource\apache-maven-3.0.4\bin\mvn.bat -X compile exec:java -Dexec.mainClass=runclass.Runme
Apache Maven 3.0.4 (r1232337; 2012-01-17 16:44:56+0800) Maven home: D:\Progs\springsource\apache-maven-3.0.4 Java version: 1.7.0_11, vendor: Oracle Corporation Java home: C:\Program Files\Java\jdk1.7.0_11\jre Default locale: zh_CN, platform encoding: GBK OS name: "windows 7", version: "6.1", arch: "amd64", family: "windows" [INFO] Error stacktraces are turned on. [DEBUG] Reading global settings from D:\Progs\springsource\apache-maven-3.0.4\conf\settings.xml [DEBUG] Reading user settings from C:\Users\weibl\.m2\settings.xml [DEBUG] Using local repository at C:\Users\weibl\.m2\repository [DEBUG] Using manager EnhancedLocalRepositoryManager with priority 10 for C:\Users\weibl\.m2\repository [INFO] Scanning for projects... [DEBUG] Extension realms for project maven-example:maven-example:jar:0.0.1-SNAPSHOT: (none) [DEBUG] Looking up lifecyle mappings for packaging jar from ClassRealm[plexus.core, parent: null] [DEBUG] Resolving plugin prefix compile exec from [org.apache.maven.plugins, org.codehaus.mojo] [DEBUG] Could not find metadata org.apache.maven.plugins/maven-metadata.xml in local (C:\Users\weibl\.m2\repository)
上面的行与cmd shell的相同启动不同，它是[DEBUG] Resolved plugin prefix exec to org.codehaus.mojo:exec-maven-plugin from repository central 。 虽然已经下载了所有必需的jar和元数据，但每次都是一样的。
记录继续：
[DEBUG] Skipped remote update check for org.apache.maven.plugins/maven-metadata.xml, locally cached metadata up-to-date. [DEBUG] Could not find metadata org.codehaus.mojo/maven-metadata.xml in local (C:\Users\weibl\.m2\repository) [DEBUG] Skipped remote update check for org.codehaus.mojo/maven-metadata.xml, locally cached metadata up-to-date. [DEBUG] Could not find metadata org.apache.maven.plugins/maven-metadata.xml in local (C:\Users\weibl\.m2\repository) [DEBUG] Could not find metadata org.codehaus.mojo/maven-metadata.xml in local (C:\Users\weibl\.m2\repository) [DEBUG] Using connector WagonRepositoryConnector with priority 0 for http://repo.maven.apache.org/maven2 [DEBUG] Using connector WagonRepositoryConnector with priority 0 for http://repo.maven.apache.org/maven2 Downloading: http://repo.maven.apache.org/maven2/org/codehaus/mojo/maven-metadata.xml Downloading: http://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-metadata.xml 3/13 KB 7/13 KB 10/13 KB 3/22 KB 10/13 KB 7/22 KB 10/13 KB 11/22 KB 10/13 KB 11/22 KB 12/13 KB 15/22 KB 12/13 KB 19/22 KB 12/13 KB 22/22 KB 12/13 KB Downloaded: http://repo.maven.apache.org/maven2/org/codehaus/mojo/maven-metadata.xml (22 KB at 15.0 KB/sec) [DEBUG] Writing resolution tracking file C:\Users\weibl\.m2\repository\org\codehaus\mojo\resolver-status.properties 13/13 KB Downloaded: http://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-metadata.xml (13 KB at 6.1 KB/sec) [DEBUG] Writing resolution tracking file C:\Users\weibl\.m2\repository\org\apache\maven\plugins\resolver-status.properties
在此行之后可能存在写入exception，因为每次都会进行此下载。 Maven报告了更高级别的错误，它无法获得compile exec所需的工件，但是（再次说）它们已经在本地maven repo中：
[INFO] ------------------------------------------------------------------------ [INFO] BUILD FAILURE [INFO] ------------------------------------------------------------------------ [INFO] Total time: 2.655s [INFO] Finished at: Sun Jan 26 13:51:56 CST 2014 [INFO] Final Memory: 8M/152M [INFO] ------------------------------------------------------------------------ [ERROR] No plugin found for prefix ' compile exec' in the current project and in the plugin groups [org.apache.maven.plugins, org.codehaus.mojo] available from the repositories [local (C:\Users\weibl\.m2\repository), central (http://repo.maven.apache.org/maven2)] -> [Help 1] org.apache.maven.plugin.prefix.NoPluginFoundForPrefixException: No plugin found for prefix ' compile exec' in the current project and in the plugin groups [org.apache.maven.plugins, org.codehaus.mojo] available from the repositories [local (C:\Users\weibl\.m2\repository), central (http://repo.maven.apache.org/maven2)] at org.apache.maven.plugin.prefix.internal.DefaultPluginPrefixResolver.resolve(DefaultPluginPrefixResolver.java:94) at org.apache.maven.lifecycle.internal.MojoDescriptorCreator.findPluginForPrefix(MojoDescriptorCreator.java:262) at org.apache.maven.lifecycle.internal.MojoDescriptorCreator.getMojoDescriptor(MojoDescriptorCreator.java:222) at org.apache.maven.lifecycle.internal.DefaultLifecycleTaskSegmentCalculator.calculateTaskSegments(DefaultLifecycleTaskSegmentCalculator.java:106) at org.apache.maven.lifecycle.internal.DefaultLifecycleTaskSegmentCalculator.calculateTaskSegments(DefaultLifecycleTaskSegmentCalculator.java:86) at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:98) at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:320) at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:156) at org.apache.maven.cli.MavenCli.execute(MavenCli.java:537) at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:196) at org.apache.maven.cli.MavenCli.main(MavenCli.java:141) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:601) at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:290) at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:230) at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:409) at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:352) [ERROR] [ERROR] [ERROR] For more information about the errors and possible solutions, please read the following articles: [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/NoPluginFoundForPrefixException
更新：确保它与Eclipse无关。 以下Java代码生成与上面类似的日志输出
import java.util.*; import java.io.*; // http://www.javaworld.com/article/2071275/core-java/when-runtime-exec---won-t.html public class MediocreExecJavac { private static void log(String message) { System.out.println(message); } public static void main(String args[]) { try { String mavenPath = "D:\\Progs\\springsource\\apache-maven-3.0.4\\bin\\mvn.bat"; String mavenOptions = "-X compile exec:java -Dexec.mainClass=runclass.Runme"; String[] cmdLine = new String[2]; cmdLine[0] = mavenPath; //cmdLine.add(mavenPath); cmdLine[1] = mavenOptions; //cmdLine.add(mavenOptions+" compile exec:java -Dexec.mainClass="+packageClass); String[] envp = new String[2]; //Map envm = new HashMap(); envp[0] = "JAVA_HOME=" + System.getProperty("java.home"); //System.getenv("JAVA_HOME"); envp[1] = "M2_HOME=" + System.getenv("MAVEN_HOME"); File workingDirectory = null; String currentDir = new File(".").getAbsolutePath(); log(currentDir); String userDir = System.getProperty("user.dir"); //User working directory ; "user.home" User home directory workingDirectory = new File(userDir); log(workingDirectory.toString()); // Runtime rt = Runtime.getRuntime(); Process proc = rt.exec(cmdLine, envp, workingDirectory); InputStream stdout = proc.getInputStream(); InputStream stderr = proc.getErrorStream(); InputStreamReader isr = new InputStreamReader(stdout); InputStreamReader isr2 = new InputStreamReader(stderr); BufferedReader br = new BufferedReader(isr); BufferedReader br2 = new BufferedReader(isr2); String line = null; System.out.println(""); while ((line = br.readLine()) != null) System.out.println(line); System.out.println(""); System.out.println(""); while ((line = br2.readLine()) != null) System.out.println(line); System.out.println(""); int exitVal = proc.waitFor(); System.out.println("Process exitValue: " + exitVal); } catch (Throwable t) { t.printStackTrace(); } } }
输出：
... [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/NoPluginFoundForPrefixException 'cmd' ڲ ⲿ Ҳ ǿ еij ļ Process exitValue: 1
通过传递一组环境变量解决Maven和Gradle问题。
见http://www.nodeclipse.org/projects/maven和http://www.nodeclipse.org/projects/gradle/