blocks|key|3248365|text|if+(somevar+==+null)+throw+new+RuntimeException();|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3248366|用适当的异常子类型替换RuntimeException()。|3248367|entityMap^0|0|1E|0|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|M|8|@]|D|@]|E|$]]|$1|H|3|-4|5|6|7|N|8|@]|D|@]|E|$]]]|I|$]]

<code>if (somevar == null) throw new RuntimeException();</code>

Replace RuntimeException() with an appropriate exception subtype.

blocks|key|407307|text|Assert在Android中是行不通的，因为大多数时候人们不是在调试模式下运行，而是在一些优化的代码中运行。因此，正确的解决方案是手动抛出异常，代码如下：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|407308|if+(obj==null)+throw+new+AssertionError("Object+cannot+be+null");|code-block|syntax|javascript|407309|应该注意，根据设计，断言是用于调试代码的，而不是用于发布时代码的。因此，这可能不是抛出断言的最佳用法。但你还是可以这样做的，所以...|407310|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Assert won't work in Android because most of the time a person isn't running in debug mode, but rather some optimized code. Thus, the proper solution is to manually throw an exception, with code like this:

<pre><code>if (obj==null) throw new AssertionError("Object cannot be null");
</code></pre>

It should be noted that by design, Asserts are intended for debug code, and not for release time code. So this might not be the best use of throwing an Assert. But this is how you can do it still, so...

blocks|key|3461740|text|在Android+4.x设备上测试，可以在Android设备上使用Java+assert：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3461741|debug.assert=1|3461742|Reboot+phone编辑//|unordered-list-item|3461743|(例如，通过X-plore)，在文件末尾添加行：X-plore+phone|offset|length|3461744|3461745|3461746|现在你的Android设备可以明智地断言检查，并在断言检查失败时抛出AssertionError。|3461747|编辑：|3461748|另一种简单的方法是从PC启用断言，直到设备重启：|3461749|platform-tools\adb+shell+setprop+debug.assert+1|code-block|syntax|javascript|3461750|例如，您可以创建一个.bat文件(在Windows上)，并在连接设备时运行它。|3461751|entityMap|0|LINK|mutability|MUTABLE|url|https://play.google.com/store/apps/details?id=com.lonelycatgames.Xplore|1^0|0|0|0|6|7|0|O|7|1|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|18|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|19|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|1A|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|1B|8|@]|9|@$I|1C|J|1D|1|1E]|$I|1F|J|1G|1|1H]]|A|$]]|$1|K|3|-4|5|6|7|1I|8|@]|9|@]|A|$]]|$1|L|3|-4|5|6|7|1J|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|1K|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|1L|8|@]|9|@]|A|$]]|$1|Q|3|R|5|6|7|1M|8|@]|9|@]|A|$]]|$1|S|3|T|5|U|7|1N|8|@]|9|@]|A|$V|W]]|$1|X|3|Y|5|6|7|1O|8|@]|9|@]|A|$]]|$1|Z|3|-4|5|6|7|1P|8|@]|9|@]|A|$]]]|10|$11|$5|12|13|14|A|$15|16]]|17|$5|12|13|14|A|$15|16]]]]

Tested on Android 4.x device, it is possible to use Java assert on Android device:

<ul>
<li>Edit /system/build.prop (for example by <a href="https://play.google.com/store/apps/details?id=com.lonelycatgames.Xplore">X-plore</a>), add line at end of file: debug.assert=1</li>
<li>Reboot phone</li>
</ul>

Now your Android device is sensible to assert checks, and will throw AssertionError when assert check fails.

EDIT:

Another easy approach, enabling asserts from PC until device is restarted:

<pre><code>platform-tools\adb shell setprop debug.assert 1
</code></pre>

You may for example create a .bat file (on Windows) and run it when device is attached.

blocks|key|407341|text|创建您自己的assert方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|407342|public+static+<T>+T+assertNotNull(T+object)+{
++++if+(object+==+null)
++++++++throw+new+AssertionError("Object+cannot+be+null");
++++return+object;
}|code-block|syntax|javascript|407343|为了简洁起见，返回相同的对象允许在赋值中使用它。|407344|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Create your own assert method:

<pre><code>public static &lt;T&gt; T assertNotNull(T object) {
 if (object == null)
 throw new AssertionError("Object cannot be null");
 return object;
}
</code></pre>

Returning same object allows for using this in assignments for brevity.

blocks|key|407350|text|分享我在Android上用于断言的类，它更简单，命名更好，非常优雅，因为它允许你像这样写断言：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|407351|Assert.that(obj!=null,+"Object+should+not+be+null");|code-block|syntax|javascript|407352|下面是该类的代码：|407353|public+class+Assert+{
++++public+static+void+that(boolean+condition,+String+message)+{
++++++++if+(!condition)+{
++++++++++++throw+new+AssertionError(message);
++++++++}
++++}
}|407354|希望它能帮上忙！|407355|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Sharing my class which I use for assertions on Android, its simpler, has nice naming and very elegant because it allows you to write asserts like this:

<pre><code>Assert.that(obj!=null, "Object should not be null");
</code></pre>

Here's the code for the class:

<pre><code>public class Assert {
 public static void that(boolean condition, String message) {
 if (!condition) {
 throw new AssertionError(message);
 }
 }
}
</code></pre>

Hope it helps!

blocks|key|410837|text|使用-enableassertions或-ea命令行选项使断言在Java虚拟机中可用|type|unstyled|depth|inlineStyleRanges|offset|length|style|BOLD|entityRanges|data|410838|410839|on+Window的命令提示符java+-ea+YourApp|unordered-list-item|410840|410841|410842|on+Android+Studio3.0，Tools/Edit+Configurations/VM+options，输入-enableassertions或-ea|410843|410844|entityMap^0|3|G|L|2|0|0|0|0|0|L|10|1P|G|27|2|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]|$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|V|8|@]|D|@]|E|$]]|$1|G|3|H|5|I|7|W|8|@]|D|@]|E|$]]|$1|J|3|-4|5|6|7|X|8|@]|D|@]|E|$]]|$1|K|3|-4|5|6|7|Y|8|@]|D|@]|E|$]]|$1|L|3|M|5|I|7|Z|8|@$9|10|A|11|B|C]|$9|12|A|13|B|C]|$9|14|A|15|B|C]]|D|@]|E|$]]|$1|N|3|-4|5|6|7|16|8|@]|D|@]|E|$]]|$1|O|3|-4|5|6|7|17|8|@]|D|@]|E|$]]]|P|$]]

To make assertion available in Java Virtual Machine, using -enableassertions or -ea command-line options 

<ul>
<li>on Window's Command prompt, 

<blockquote>
 java –ea YourApp
</blockquote></li>
<li>on Android Studio 3.0, on Tools/Edit Configurations/VM options, input -enableassertions or -ea</li>
</ul>

I want to use <code>assert obj != null : "object cannot be null"</code> on Android device. The assert doesn't seem to work, so I searched online and I found this local solution: 

<blockquote>
 adb shell setprop debug.assert 1
</blockquote>

it does work on my local machine.

I want to run this command using my Eclipse project(so it would be in the source control).
How can I do it?

How to use assert in android?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我想在安卓设备上使用assert obj != null : "object cannot be null"。断言似乎不起作用，所以我在网上搜索，找到了这个本地解决方案： adb shell setprop debug.assert 1它可以在我的本地机器上工作。我想使用我的Eclipse项目运行这个命令(所以它应该在...

问如何在android中使用assert？
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