android studio在编辑时出现如Failed to sync Gradle project类似的问题时的解决方案

最近使用android studio发现环境坏了，提示如下：

Failedto sync Gradle project’XXXXX’

Error:Unable to load class'asLocalRepo0_1r7i3nvnipez3xbls4oy6h797'.

Possible causes for this unexpected errorinclude:

• You are using JDK version 'java version"1.7.0_67"'. Some versions of JDK 1.7 (e.g. 1.7.0_10) may cause classloading errors in Gradle.

  Please update to a newer version (e.g.1.7.0_67).

  OpenJDK Settings

• Gradle's dependency cache may becorrupt (this sometimes occurs after a network connection timeout.)

  Re-download dependencies and sync project(requires network)

• The state of a Gradle buildprocess (daemon) may be corrupt. Stopping all Gradle daemons may solve thisproblem.

  Stop Gradle build processes (requiresrestart)

• Your project may be using a third-partyplugin which is not compatible with the other plugins in the project or theversion of Gradle requested by the project.

In the case ofcorrupt Gradle processes, you can also try closing the IDE and then killing allJava processes.

按上面的意思，可能是jdk出问题了，所以查看了一下自己的jdk版本:1.7.0.67，已经是了呀，后来我读这段英语才明白，它的意思是jdk1.7(无论是1.7.0_10还是1.7.0.67，还是别的1.7.XXX)类型的可能都会导致使用Gradle工具类加载错误，所以就去下载个最新版的吧，我写的现在最新版是jdk 1.8,下载地址: http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

如图:

安装配置请参考：http://jingyan.baidu.com/article/f96699bb8b38e0894e3c1bef.html

对于下载安装配置完jdk1.8，我在项目目录\app\build.gradle里面写的还是1.7：

sourceCompatibilityJavaVersion.VERSION_1_7

targetCompatibilityJavaVersion.VERSION_1_7

一开始是我写成了1.8的如:

sourceCompatibilityJavaVersion.VERSION_1_8

targetCompatibilityJavaVersion.VERSION_1_8

报了很多莫名其妙的错如：

UNEXPECTEDTOP-LEVEL EXCEPTION:

Error:com.android.dx.cf.iface.ParseException:bad class file magic (cafebabe) or version (0034.0000)

         atcom.android.dx.cf.direct.DirectClassFile.parse0(DirectClassFile.java:472)

         atcom.android.dx.cf.direct.DirectClassFile.parse(DirectClassFile.java:406)

         at com.android.dx.cf.direct.DirectClassFile.parseToInterfacesIfNecessary(DirectClassFile.java:388)

         atcom.android.dx.cf.direct.DirectClassFile.getMagic(DirectClassFile.java:251)

         atcom.android.dx.command.dexer.Main.parseClass(Main.java:764)

         at com.android.dx.command.dexer.Main.access$1500(Main.java:85)

         atcom.android.dx.command.dexer.Main$ClassParserTask.call(Main.java:1684)

         atcom.android.dx.command.dexer.Main.processClass(Main.java:749)

         ... 19 more

出现这种错，可能是jdk1.8虽然比jdk1.7更兼容，但他们使用的某些库和函数差别比较，当然有兄弟知道的更多的，也请告诉我一声，谢谢了。

 

然后再重新加载时就少了这个错，

OpenJDK Settings

Gradle's dependency cache may becorrupt (this sometimes occurs after a network connection timeout.)

Re-download dependencies and sync project(requires network)

The state of a Gradle buildprocess (daemon) may be corrupt. Stopping all Gradle daemons may solve thisproblem.

Stop Gradle build processes (requiresrestart)

Your project may be using a third-partyplugin which is not compatible with the other plugins in the project or theversion of Gradle requested by the project.

In the case ofcorrupt Gradle processes, you can also try closing the IDE and then killing allJava processes.

 

对于这个问题，观察和猜想，关键应该是这句话：Your project may be using a third-party plugin which is notcompatible with the other plugins in the project or the version of Gradlerequested by the project，我的理解就是插件不兼容，再看看了官网，然后把咱们的项目下的build.gradle下面的改成最新的，我的是改成这样：

 

再设置一下:项目目录\gradle\wrapper\gradle-wrapper.properties这个文件的distributionUrl=https\://services.gradle.org/distributions/gradle-2.9-all.zip，如果不知道设置成什么的话，就设置比较新吧，那么怎么知道现在有哪些新的gradle包呢?请访问这个地址：

https://services.gradle.org/distributions/如下图：

我选择的是第二个，再重新编译就没有这个问题了，不过，我又出现新问题了:

……

Error:(17, 0) Gradle DSL method not found: 'android()'如图

我想了想，发现之前的项目顶级目录的build.gradle这个文件里面只有：

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:1.5.0'
    }
}
allprojects {
    repositories {
        jcenter()
    }
}

所以把这些之外，17行开始android{}的相关内容删除后，就可以了。