Andriod Studio更新之后打开打开Android Device Monitor失败

前提：因为工作电脑卡的不行，所以系统硬盘就切换为固态硬盘，就重装系统了，升级完了之后，觉得焕然一新，轻松+愉快;前几天准备用Android Device Monitor，却发现打不开直接报错了（囧哭）
正好国庆前一天，工作不是很紧张，就把先这个问题解决了，避免影响之后的工作

报错log（在目录sdk/tools/lib/monitor-x86_64/×××.log）

!ENTRY org.eclipse.osgi 4 0 2017-09-30 16:23:09.769
!MESSAGE Application error
!STACK 1
org.eclipse.core.runtime.CoreException: Plug-in com.android.ide.eclipse.monitor was unable to load class com.android.ide.eclipse.monitor.MonitorApplication.
    at org.eclipse.core.internal.registry.osgi.RegistryStrategyOSGI.throwException(RegistryStrategyOSGI.java:194)
    at org.eclipse.core.internal.registry.osgi.RegistryStrategyOSGI.createExecutableExtension(RegistryStrategyOSGI.java:176)
    at org.eclipse.core.internal.registry.ExtensionRegistry.createExecutableExtension(ExtensionRegistry.java:905)
    at org.eclipse.core.internal.registry.ConfigurationElement.createExecutableExtension(ConfigurationElement.java:243)
    at org.eclipse.core.internal.registry.ConfigurationElementHandle.createExecutableExtension(ConfigurationElementHandle.java:55)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:191)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:353)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:180)
    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:606)
    at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1438)
    at org.eclipse.equinox.launcher.Main.main(Main.java:1414)
Caused by: org.eclipse.core.runtime.internal.adaptor.EclipseLazyStarter$TerminatingClassNotFoundException: An error occurred while automatically activating bundle com.android.ide.eclipse.monitor (5).
    at org.eclipse.core.runtime.internal.adaptor.EclipseLazyStarter.postFindLocalClass(EclipseLazyStarter.java:122)
    at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findLocalClass(ClasspathManager.java:469)
    at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.findLocalClass(DefaultClassLoader.java:216)
    at org.eclipse.osgi.internal.loader.BundleLoader.findLocalClass(BundleLoader.java:395)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:464)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:421)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:412)
    at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
    at org.eclipse.osgi.internal.loader.BundleLoader.loadClass(BundleLoader.java:340)
    at org.eclipse.osgi.framework.internal.core.BundleHost.loadClass(BundleHost.java:229)
    at org.eclipse.osgi.framework.internal.core.AbstractBundle.loadClass(AbstractBundle.java:1212)
    at org.eclipse.core.internal.registry.osgi.RegistryStrategyOSGI.createExecutableExtension(RegistryStrategyOSGI.java:174)
    ... 16 more
Caused by: org.osgi.framework.BundleException: The activator com.android.ide.eclipse.monitor.MonitorPlugin for bundle com.android.ide.eclipse.monitor is invalid
    at org.eclipse.osgi.framework.internal.core.AbstractBundle.loadBundleActivator(AbstractBundle.java:172)
    at org.eclipse.osgi.framework.internal.core.BundleContextImpl.start(BundleContextImpl.java:679)
    at org.eclipse.osgi.framework.internal.core.BundleHost.startWorker(BundleHost.java:381)
    at org.eclipse.osgi.framework.internal.core.AbstractBundle.start(AbstractBundle.java:300)
    at org.eclipse.osgi.framework.util.SecureAction.start(SecureAction.java:440)
    at org.eclipse.osgi.internal.loader.BundleLoader.setLazyTrigger(BundleLoader.java:263)
    at org.eclipse.core.runtime.internal.adaptor.EclipseLazyStarter.postFindLocalClass(EclipseLazyStarter.java:107)
    ... 28 more
Caused by: java.lang.UnsupportedClassVersionError: com/android/prefs/AndroidLocation$AndroidLocationException : Unsupported major.minor version 52.0
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:803)
    at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.defineClass(DefaultClassLoader.java:188)
    at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.defineClassHoldingLock(ClasspathManager.java:632)
    at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.defineClass(ClasspathManager.java:607)
    at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findClassImpl(ClasspathManager.java:568)
    at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findLocalClassImpl(ClasspathManager.java:492)
    at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findLocalClass(ClasspathManager.java:465)
    at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.findLocalClass(DefaultClassLoader.java:216)
    at org.eclipse.osgi.internal.loader.BundleLoader.findLocalClass(BundleLoader.java:395)
    at org.eclipse.osgi.internal.loader.SingleSourcePackage.loadClass(SingleSourcePackage.java:35)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:461)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:421)
    at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:412)
    at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
    at com.android.ide.eclipse.monitor.MonitorPlugin.<clinit>(MonitorPlugin.java:28)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
    at java.lang.Class.newInstance(Class.java:383)
    at org.eclipse.osgi.framework.internal.core.AbstractBundle.loadBundleActivator(AbstractBundle.java:167)
    ... 34 more

根据log google搜索解决方案

先根据下面log关键字搜索

Caused by: java.lang.UnsupportedClassVersionError: com/android/prefs/AndroidLocation$AndroidLocationException : Unsupported major.minor version 52.0

https://stackoverflow.com/questions/42661578/android-device-monitor-will-not-launch-either-from-android-studio-or-from-termi
给出的解决方式是：安装java8
于是将本地的java7，切换为java8，但是依旧无效;

切换关键字搜索：

org.eclipse.core.runtime.CoreException: Plug-in com.android.ide.eclipse.monitor was unable to load class com.android.ide.eclipse.monitor.MonitorApplication.、

https://issuetracker.google.com/issues/36970884
给出的解决方案是下载SDK之前老的版本,文档里有给出可以老的sdk版本
Currently the only workaround is to download the previous version of SDK separately, and replace the contents of tools/lib/monitor folder with the one from the previous version. You can get the previous version here:

https://dl.google.com/android/android-sdk_r21.1-windows.zip
https://dl.google.com/android/android-sdk_r21.1-macosx.zip
https://dl.google.com/android/android-sdk_r21.1-linux.tgz

亲证，替换sdk/tools文件夹即可成功打开Android Device Monitor

后记

将java8 切换至java7之后，依旧有效，看来这个问题跟java版本没有问题

作为Android新进菜鸟一枚，多谢大神们给出的解决方案，虽只是搬运别人的想法，但整理到自己的博客是为了方便遇到此类问题能够快速找到解决方案