blocks|key|298433|text|此外，枚举可以实现接口。您可以添加一些get()方法，如getMaxSpeed()或getWeight()。接口可能如下所示：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|298434|interface+car{
public+int+getMaxSpeed();
public+int+getWeight();
}|code-block|syntax|javascript|298435|entityMap^0|J|5|S|D|16|B|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|U|8|@]|D|@]|E|$]]]|L|$]]

Moreover enums can implement an interface. You can add some <code>get()</code> methods like <code>getMaxSpeed()</code> or <code>getWeight()</code>.
Interface can look like

<pre><code>interface car{
public int getMaxSpeed();
public int getWeight();
}
</code></pre>

blocks|key|298437|text|你可以做这样的事情。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|298438|public+enum+CarModel+{
++++DIABLO("Lamborghini",+"Italy"),
++++P911("Porsche",+"Germany");

++++private+String+manufacturer;
++++private+String+country;

++++private+CarModel(String+manufacturer,+String+country)+{
++++++++this.manufacturer+=+manufacturer;
++++++++this.country+=+country;
++++}

++++public+String+getManufacturer()+{
++++++++return+manufacturer;
++++}

++++public+String+getCountry()+{
++++++++return+country;
++++}
}|code-block|syntax|javascript|298439|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|$]]

You can do something like this.

<pre><code>public enum CarModel {
 DIABLO("Lamborghini", "Italy"),
 P911("Porsche", "Germany");

 private String manufacturer;
 private String country;

 private CarModel(String manufacturer, String country) {
 this.manufacturer = manufacturer;
 this.country = country;
 }

 public String getManufacturer() {
 return manufacturer;
 }

 public String getCountry() {
 return country;
 }
}
</code></pre>

blocks|key|298473|text|是的，完全正确。枚举可以有自己的方法，这些方法可以是特定于值的。它看起来是这样的：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|298474|enum+CarModel+{
++++P911+{
++++++++public+String+getManufacturer()+{+return+"Porsche";+}
++++},
++++DB7+{
++++++++public+String+getManufacturer()+{+return+"Aston+Martin";+}
++++},
++++...
++++public+abstract+String+getManufacturer();
}|code-block|syntax|javascript|298475|当然，您可以添加更多方法。|298476|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|$]]

Yes, absolutely. Enums can have their own methods, and those methods can be value-specific. It looks like this:

<pre><code>enum CarModel {
 P911 {
 public String getManufacturer() { return "Porsche"; }
 },
 DB7 {
 public String getManufacturer() { return "Aston Martin"; }
 },
 ...
 public abstract String getManufacturer();
}
</code></pre>

You can add more methods, of course.

blocks|key|298497|text|是的，这很容易做到：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|298498|public+enum+CarModel+{
++++DIABLO("rod"),
++++P911("jane"),
++++DB7("freddy");

++++private+String+name;
++++CarModel(String+name){
++++++++this.name+=+name;
++++}

++++public+String+getName()+{
++++++++return+name;
++++}
}+++|code-block|syntax|javascript|298499|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|$]]

Yes, this is quite easy to do:

<pre><code>public enum CarModel {
 DIABLO("rod"),
 P911("jane"),
 DB7("freddy");

 private String name;
 CarModel(String name){
 this.name = name;
 }

 public String getName() {
 return name;
 }
} 
</code></pre>

blocks|key|298540|text|我建议将此信息直接添加到枚举中。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|298541|如下所示：|298542|public+enum+CarModel+{

++++DIABLO("Lambo"),
++++P911+("Porsche");

++++private+String+manufacturer;


++++private+CarModel(String+manufacturer)+{
++++++++this.manufacturer+=+manufacturer;
++++}

++++public+String+getManufacturer()+{
++++++++return+manufacturer;
++++}++++
}|code-block|syntax|javascript|298543|在这个类中，您只需使用getManufacturer方法|298544|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|O|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

I would suggest adding this information directly into your enum.

Like this:

<pre><code>public enum CarModel {

 DIABLO("Lambo"),
 P911 ("Porsche");

 private String manufacturer;


 private CarModel(String manufacturer) {
 this.manufacturer = manufacturer;
 }

 public String getManufacturer() {
 return manufacturer;
 } 
}
</code></pre>

and in the class you'd only have to use the getManufacturer method

blocks|key|515191|text|哈哈，我推荐你使用“工厂”设计模式。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|515192|你可以做一个CarFactory()，来生产新的模型汽车。|515193|http://en.wikipedia.org/wiki/Factory_method_pattern|offset|length|515194|entityMap|0|LINK|mutability|MUTABLE|url^0|0|0|0|1F|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|Q|8|@]|9|@$F|R|G|S|1|T]]|A|$]]|$1|H|3|-4|5|6|7|U|8|@]|9|@]|A|$]]]|I|$J|$5|K|L|M|A|$N|E]]]]

Haha, I recommend you to use "Factory" Design Pattern.

you can make a CarFactory(), to produce new model car.

<a href="http://en.wikipedia.org/wiki/Factory_method_pattern" rel="nofollow">http://en.wikipedia.org/wiki/Factory_method_pattern</a>

I have an enum type (say for arguments sake <code>CarModel</code>), used throughout an application (numerous classes).

<pre><code>public enum CarModel {
 DIABLO,
 P911,
 DB7;
}
</code></pre>

I have various methods that use this <code>CarModel</code> enum type in different ways, and each has a switch statement to set some <code>String</code> variable depending on the enum type, before going on to do other stuff. (e.g. set the Manufacturer of some model, or set the country of origin etc. These results are static at runtime)

The issue is, if I want to add a new model to the enum, I'd need to go to each method, and extend/modify the switch statement to handle its existence. This could easily lead to human error, and/or code duplication (if various methods use the same switch statements).

Rather than using switch statements all-over, I would like to have static methods, that could be edited in a single location, and would allow for behaviour similar to the following:

<pre><code>String country = CarModel.DIABLO.getCountry() // returns Italy
String manufacturer = CarModel.P911.getManufacturer() // returns Porsche
</code></pre>

Is this possible with an enum, (and is an enum even the 'correct' way to do this?

get() methods in Java enum type

我有一个枚举类型(比如CarModel的参数)，在整个应用程序(许多类)中使用。public enum CarModel {    DIABLO,    P911,    DB7;}我有不同的方法以不同的方式使用这种CarModel枚举类型，每个方法都有一个switch语句来根据枚举类型设置一些String变量，然后再...

问Java枚举类型中的get()方法
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