小编sha*_*ihe的帖子

在JDK源代码中java.lang.String.toCharArray,它不Arrays.copyOf用于实现它,它说:

由于类初始化顺序问题,无法使用Arrays.copyOf

什么是"类初始化顺序问题"？

public char[] toCharArray() {
    // Cannot use Arrays.copyOf because of class initialization order issues
    char result[] = new char[value.length];
    System.arraycopy(value, 0, result, 0, value.length);
    return result;
}

我正在测试9补丁图像.
在一切正常之前,我将drawable文件重命名ic_button_beat_box_default.png为ic_button_beat_box_default.9.png,然后我得到错误:

某些文件崩溃失败,请参阅日志以获取详细信息

.然后我重新命名,它正常工作.那怎么会这样呢？

完整的错误是:

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:mergeDebugResources'.
> Some file crunching failed, see logs for details

* Try:
Run with --info or --debug option to get more log output.

* Exception is:
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:mergeDebugResources'.
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:69)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:46)
    at org.gradle.api.internal.tasks.execution.PostExecutionAnalysisTaskExecuter.execute(PostExecutionAnalysisTaskExecuter.java:35)
    ...
Caused by: java.lang.RuntimeException: Some file crunching failed, see logs for details
    at com.android.builder.png.QueuedCruncher.waitForAll(QueuedCruncher.java:260)
    at com.android.builder.png.QueuedCruncher.end(QueuedCruncher.java:280)
    at …

当我开始jvm(jdk 8)时,我发现这个cms gc日志.它显示老一代使用0K(0K(1747648K)),但jvm执行cms collect.为什么？

2019-01-31T18:00:28.603+0800: 4.466: [GC (CMS Initial Mark) [1 CMS-initial-mark: 0K(1747648K)] 65577K(2534080K), 0.0077440 secs] [Times: user=0.03 sys=0.00, real=0.01 secs] 
2019-01-31T18:00:28.611+0800: 4.474: [CMS-concurrent-mark-start]
2019-01-31T18:00:28.627+0800: 4.490: [CMS-concurrent-mark: 0.016/0.016 secs] [Times: user=0.06 sys=0.01, real=0.02 secs] 
2019-01-31T18:00:28.627+0800: 4.490: [CMS-concurrent-preclean-start]
2019-01-31T18:00:28.630+0800: 4.493: [CMS-concurrent-preclean: 0.003/0.003 secs] [Times: user=0.01 sys=0.00, real=0.00 secs] 
2019-01-31T18:00:28.630+0800: 4.493: [CMS-concurrent-abortable-preclean-start]
2019-01-31T18:00:29.748+0800: 5.611: [CMS-concurrent-abortable-preclean: 0.824/1.117 secs] [Times: user=4.06 sys=0.13, real=1.12 secs] 
2019-01-31T18:00:29.749+0800: 5.612: [GC (CMS Final Remark) [YG occupancy: 437791 K (786432 K)]2019-01-31T18:00:29.749+0800: 5.612: [Rescan (parallel) , 0.2379222 secs]2019-01-31T18:00:29.987+0800: …

我测试我的github网站具有杰基尔,但是当我添加一个新的职位是不是产生在后_posts的文件夹,所以无法获得site.posts的index.html.我jekyll serve在当地跑步.

我的文件夹:

本地页面:

本地的:

但是,它在github网站上运行良好.所以有什么问题？

这个问题我找不到任何东西。

jdk 8中JVM代码缓存区域是否存在于堆或元空间中？

在这个 HelloWorld 应用程序中，我使用了该android:colorBackground属性，但它没有应用红色背景。

AndroidManifest.xml :

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:supportsRtl="true"
    android:theme="@style/AppTheme" >
    <activity
        android:name=".EditTextActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
</application>

布局xml：

<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".EditTextActivity">

    <TextView
        android:text="Hello World!"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="40sp"
        />
</RelativeLayout>

样式.xml :

<resources>
    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
        <item name="android:colorBackground">#ff0000</item>
    </style>
</resources>

结果如下（没有红色背景）：