blocks|key|801949|text|请注意：http://download.oracle.com/javase/tutorial/extra/generics/methods.html|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|801950|下面是对模板方法的解释。|801951|entityMap|0|LINK|mutability|MUTABLE|url|http://download.oracle.com/javase/tutorial/extra/generics/methods.html^0|4|1Y|0|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@$A|O|B|P|1|Q]]|C|$]]|$1|D|3|E|5|6|7|R|8|@]|9|@]|C|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|C|$]]]|G|$H|$5|I|J|K|C|$L|M]]]]

Se these:
<a href="http://download.oracle.com/javase/tutorial/extra/generics/methods.html" rel="nofollow">http://download.oracle.com/javase/tutorial/extra/generics/methods.html</a>

here is the explaniation for the template methods.

blocks|key|1016458|text|使用|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1016459|void+callClass(Class+classObject)
{
+++//do+something+with+class
}|code-block|syntax|javascript|1016460|Class也是一个Java对象，所以您可以使用它的类型来引用它。|offset|length|style|CODE|1016461|从official+documentation阅读更多关于它的信息。|1016462|entityMap|0|LINK|mutability|MUTABLE|url|http://download.oracle.com/javase/1.5.0/docs/api/java/lang/Class.html^0|0|0|0|5|0|1|M|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Y|8|@$I|Z|J|10|K|L]]|9|@]|A|$]]|$1|M|3|N|5|6|7|11|8|@]|9|@$I|12|J|13|1|14]]|A|$]]|$1|O|3|-4|5|6|7|15|8|@]|9|@]|A|$]]]|P|$Q|$5|R|S|T|A|$U|V]]]]

Use

<pre><code>void callClass(Class classObject)
{
 //do something with class
}
</code></pre>

A <code>Class</code> is also a Java object, so you can refer to it by using its type.

Read more about it from <a href="http://download.oracle.com/javase/1.5.0/docs/api/java/lang/Class.html" rel="nofollow">official documentation</a>.

blocks|key|1016493|text|看看反射教程和Java的反射API：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1016494|https://community.oracle.com/docs/DOC-983192enter+link+description+here|offset|length|1016495|和|1016496|http://docs.oracle.com/javase/6/docs/api/java/lang/Class.html|1016497|entityMap|0|LINK|mutability|MUTABLE|url|https://community.oracle.com/docs/DOC-983192|1|2^0|0|0|18|0|18|R|1|0|0|0|1P|2|0^^$0|@$1|2|3|4|5|6|7|T|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|U|8|@]|9|@$D|V|E|W|1|X]|$D|Y|E|Z|1|10]]|A|$]]|$1|F|3|G|5|6|7|11|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|12|8|@]|9|@$D|13|E|14|1|15]]|A|$]]|$1|J|3|-4|5|6|7|16|8|@]|9|@]|A|$]]]|K|$L|$5|M|N|O|A|$P|Q]]|R|$5|M|N|O|A|$P|Q]]|S|$5|M|N|O|A|$P|I]]]]

Have a look at the reflection tutorial and reflection API of Java:

<a href="https://community.oracle.com/docs/DOC-983192" rel="nofollow noreferrer">https://community.oracle.com/docs/DOC-983192</a><a href="https://community.oracle.com/docs/DOC-983192" rel="nofollow noreferrer">enter link description here</a>

and 

<a href="http://docs.oracle.com/javase/6/docs/api/java/lang/Class.html" rel="nofollow noreferrer">http://docs.oracle.com/javase/6/docs/api/java/lang/Class.html</a>

blocks|key|1016562|text|正如您所说，GWT不支持反射。你应该使用延迟绑定而不是反射，或者像gwt-ent这样的第三方库来支持gwt层的反射。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1016563|entityMap|0|LINK|mutability|MUTABLE|url|http://code.google.com/p/gwt-ent/^0|X|7|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

As you said GWT does not support reflection. You should use deferred binding instead of reflection, or third party library such as <a href="http://code.google.com/p/gwt-ent/" rel="nofollow">gwt-ent</a> for reflection suppport at gwt layer.

blocks|key|802169|text|我不确定你想完成什么，但你可能想要考虑一下，通过一个类可能并不是你真正需要做的事情。在许多情况下，像这样处理Class很容易封装在某种类型的工厂模式中，并且可以通过接口使用它。这里是关于该模式的几十篇文章中的一篇：http://today.java.net/pub/a/today/2005/03/09/factory.html|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|802170|在工厂中使用类可以通过多种方式完成，最值得注意的是拥有一个配置文件，其中包含实现所需接口的类的名称。然后，工厂可以从类路径中找到该类，并将其构造为指定接口的对象。|802171|entityMap|0|LINK|mutability|MUTABLE|url|http://today.java.net/pub/a/today/2005/03/09/factory.html^0|2Z|1L|0|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@$A|O|B|P|1|Q]]|C|$]]|$1|D|3|E|5|6|7|R|8|@]|9|@]|C|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|C|$]]]|G|$H|$5|I|J|K|C|$L|M]]]]

I am not sure what you are trying to accomplish, but you may want to consider that passing a class may not be what you really need to be doing. In many cases, dealing with Class like this is easily encapsulated within a factory pattern of some type and the use of that is done through an interface. here's one of dozens of articles on that pattern: <a href="http://today.java.net/pub/a/today/2005/03/09/factory.html" rel="nofollow">http://today.java.net/pub/a/today/2005/03/09/factory.html</a>

using a class within a factory can be accomplished in a variety of ways, most notably by having a config file that contains the name of the class that implements the required interface. Then the factory can find that class from within the class path and construct it as an object of the specified interface.

blocks|key|1017086|text|public+void+callingMethod(Class+neededClass)+{
++++//Cast+the+class+to+the+class+you+need
++++//and+call+your+method+in+the+class
++++((ClassBeingCalled)neededClass).methodOfClass();
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1017087|要调用该方法，您可以这样调用它：|unstyled|1017088|callingMethod(ClassBeingCalled.class);|1017089|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|L|8|@]|9|@]|A|$]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$B|C]]|$1|I|3|-4|5|F|7|N|8|@]|9|@]|A|$]]]|J|$]]

<pre><code>public void callingMethod(Class neededClass) {
 //Cast the class to the class you need
 //and call your method in the class
 ((ClassBeingCalled)neededClass).methodOfClass();
}
</code></pre>

To call the method, you call it this way:

<pre><code>callingMethod(ClassBeingCalled.class);
</code></pre>

blocks|key|1017185|text|构造你的方法来接受它-|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1017186|public+<T>+void+printClassNameAndCreateList(Class<T>+className){
++++//example+access+1
++++System.out.print(className.getName());

++++//example+access+2
++++ArrayList<T>+list+=+new+ArrayList<T>();
++++//note+that+if+you+create+a+list+this+way,+you+will+have+to+cast+input
++++list.add((T)nameOfObject);
}|code-block|syntax|javascript|1017187|调用该方法-|1017188|printClassNameAndCreateList(SomeClass.class);|1017189|您还可以限制类的类型，例如，这是我创建的库中的一个方法-|1017190|protected+Class+postExceptionActivityIn;

protected+<T+extends+PostExceptionActivity>++void++setPostExceptionActivityIn(Class+<T>+postExceptionActivityIn)+{
++++this.postExceptionActivityIn+=+postExceptionActivityIn;
}|1017191|有关更多信息，请搜索反射和泛型。|1017192|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|W|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|Y|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

Construct your method to accept it-

<pre><code>public &lt;T&gt; void printClassNameAndCreateList(Class&lt;T&gt; className){
 //example access 1
 System.out.print(className.getName());

 //example access 2
 ArrayList&lt;T&gt; list = new ArrayList&lt;T&gt;();
 //note that if you create a list this way, you will have to cast input
 list.add((T)nameOfObject);
}
</code></pre>

Call the method-

<pre><code>printClassNameAndCreateList(SomeClass.class);
</code></pre>

You can also restrict the type of class, for example, this is one of the methods from a library I made-

<pre><code>protected Class postExceptionActivityIn;

protected &lt;T extends PostExceptionActivity&gt; void setPostExceptionActivityIn(Class &lt;T&gt; postExceptionActivityIn) {
 this.postExceptionActivityIn = postExceptionActivityIn;
}
</code></pre>

For more information, search Reflection and Generics.

blocks|key|1017641|text|添加T作为返回类型对我来说很有效。使用json反序列化的Ex|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1017642|+public+static+<T>+T+fromJson(String+json,+Class<T>+classOfT){
+++++return+gson().fromJson(json,+classOfT);
+}|code-block|syntax|javascript|1017643|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Adding &lt;T&gt; T as return type worked for me. Ex with json deserialize
<pre><code> public static &lt;T&gt; T fromJson(String json, Class&lt;T&gt; classOfT){
 return gson().fromJson(json, classOfT);
 }
</code></pre>

Is there any way to pass class as a parameter in Java and fire some methods from that class?

<pre><code>void main()
{
 callClass(that.class)
}

void callClass(???? classObject)
{
 classObject.somefunction
 // or 
 new classObject()
 //something like that ?
}
</code></pre>

I am using Google Web Toolkit and it does not support reflection.

How do I pass a class as a parameter in Java?

有没有办法在Java中将class作为参数传递，并从该类中触发一些方法？void main(){    callClass(that.class)}void callClass(???? classObject){    classObject.somefunction    // or     new classOb...

问如何在Java中将类作为参数传递？
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