blocks|key|754581|text|正如Oracle文档中所描述的，|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|754582|枚举类型是一种特殊的数据类型，它允许变量成为一组预定义的常量。|blockquote|754583|常量的名称必须满足与任何变量相同的规则，因此它不能是整数。|754584|样式约定是将常量写成大写，单词之间用下划线隔开。|754585|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.oracle.com/javase/tutorial/java/javaOO/enum.html|1|https://docs.oracle.com/javase/tutorial/java/nutsandbolts/variables.html^0|2|8|0|0|0|H|2|1|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@$A|V|B|W|1|X]]|C|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|C|$]]|$1|G|3|H|5|6|7|Z|8|@]|9|@$A|10|B|11|1|12]]|C|$]]|$1|I|3|J|5|6|7|13|8|@]|9|@]|C|$]]|$1|K|3|-4|5|6|7|14|8|@]|9|@]|C|$]]]|L|$M|$5|N|O|P|C|$Q|R]]|S|$5|N|O|P|C|$Q|T]]]]

As described in <a href="https://docs.oracle.com/javase/tutorial/java/javaOO/enum.html" rel="nofollow">Oracle's documentation</a>,

<blockquote>
 An enum type is a special data type that enables for a variable to be
 a set of predefined constants.
</blockquote>

The names of the constants must satisfy the same <a href="https://docs.oracle.com/javase/tutorial/java/nutsandbolts/variables.html" rel="nofollow">rules</a> as any variable, therefore it cannot be an integer. 

The style convention is to write constants as uppercase with words separated by underscores.

blocks|key|755558|text|Enum是以大写字母命名的实例数量有限的类。用单词写出数字，而不是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|755559|public+enum+MyList+{
++++ONE,
++++TWO,
++++THREE,
++++APPLE,
++++BANANA
}|code-block|syntax|javascript|755560|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|$]]

Enum is the kind of class with the limited number of its instances named with capital letters. Write the numbers with words out instead:

<pre><code>public enum MyList {
 ONE,
 TWO,
 THREE,
 APPLE,
 BANANA
}
</code></pre>

blocks|key|1455193|text|Enum是特殊的数据类型，它只包含大写的常量值，如public+enum+myList{+APPLE,+BANANA+}。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1455194|因此，所有这些常量都是变量名，不能以数字开头(例如，1+1APPLE作为var名称，变量可以以字母表或下划线开头)。记住如何在java中命名变量。|1455195|entityMap^0|P|Z|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|$]]

Enums are special data types which contains only constant values in upper case like<code>public enum myList{
APPLE,
BANANA
}</code>

So all these constants are variable names which cannot start a name with number(like 1APPLE as var name, a variable can start with an alphabet or underscore). Remember how variables can be named in java.

blocks|key|754621|text|您可以创建如下所示的自定义枚举类型|type|unstyled|depth|inlineStyleRanges|entityRanges|data|754622|public+enum+MyList{

++++ONE(1),+TWO(2),+THREE(3),+APPLE("apple"),+BANANA("banana");

++++Object+myItem;

++++private+MyList(Object+myItem)+{
++++++++this.myItem=+myItem;
++++}

+public+static+MyList+customValueOf(Object+value)+{
++++++++for(MyList+v+:+values())
++++++++++++if(v.myItem.equalsIgnoreCase(value))+return+v;
++++++++throw+new+IllegalArgumentException();
++++}

}|code-block|syntax|javascript|754623|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 create a custom enum type like below , 

<pre><code>public enum MyList{

 ONE(1), TWO(2), THREE(3), APPLE("apple"), BANANA("banana");

 Object myItem;

 private MyList(Object myItem) {
 this.myItem= myItem;
 }

 public static MyList customValueOf(Object value) {
 for(MyList v : values())
 if(v.myItem.equalsIgnoreCase(value)) return v;
 throw new IllegalArgumentException();
 }

}
</code></pre>

blocks|key|754627|text|对于需要它的单个枚举值，您可以重写toString()，如下所示：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|754628|public+enum+MyList+{
++++E1+{+@Override+public+String+toString()+{+return+"1";+}+},
++++E2+{+@Override+public+String+toString()+{+return+"2";+}+},
++++E3+{+@Override+public+String+toString()+{+return+"3";+}+},
++++APPLE,
++++BANANA
}|code-block|syntax|javascript|754629|缺点是，您必须始终使用myEnumVal.toString()来获取枚举的字符串表示，而不是myEnumVal.name()。如果需要字符串到MyList转换，可以添加如下静态函数：|offset|length|style|CODE|754630|public+static+MyList+fromValue(String+v)+{
++++for+(MyList+e:+MyList.values())+{
++++++++if+(e.toString().equals(v))+{
++++++++++++return+e;
++++++++}
++++}
++++throw+new+IllegalArgumentException(v);
}|754631|entityMap^0|0|0|B|K|1A|G|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@$I|T|J|U|K|L]|$I|V|J|W|K|L]]|9|@]|A|$]]|$1|M|3|N|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|P|$]]

You might override the toString() for individual enum values that need it, like this:

<pre><code>public enum MyList {
 E1 { @Override public String toString() { return "1"; } },
 E2 { @Override public String toString() { return "2"; } },
 E3 { @Override public String toString() { return "3"; } },
 APPLE,
 BANANA
}
</code></pre>

The downside is that you would always have to use <code>myEnumVal.toString()</code> to get the string representation of the enum instead of <code>myEnumVal.name()</code>. If you need String to MyList conversions, you might add a static function like this:

<pre><code>public static MyList fromValue(String v) {
 for (MyList e: MyList.values()) {
 if (e.toString().equals(v)) {
 return e;
 }
 }
 throw new IllegalArgumentException(v);
}
</code></pre>

I have a problem regarding how can I put an integer value as well as a string in an enum class. I'm using the values of the enum to be stored in the database. What I want is something like this

<pre><code>public enum MyList {
 1,
 2,
 3,
 APPLE,
 BANANA
}
</code></pre>

but i have an error in the value '1', it says

<pre><code>Syntax error on token "1", Identifier expected
</code></pre>

I've searched for answers here but what I've found is they try to get the value of the enum based on the input integer from the user. What I need is to directly store the values <code>1</code>,<code>2</code>, <code>3</code>, <code>APPLE</code> and <code>BANANA</code> in the database.

Is it even possible to combine an integer and a string in an enum? Any help or suggestions would be a great help. Thanks a lot!

PS. I'm very new to programming, so it's quite hard for me to explain the problem using the correct terms. Kindly reply using simple terms! Thank you!

EDIT:

If <code>1</code> is the only integer at the said class, the error is like what I've said above. But after I added <code>2</code> and <code>3</code>, it has a red line in <code>public enum MyList {</code> and says

<pre><code>Syntax error on token(s), misplaced construct(s)
</code></pre>

an integer and string in an enum class

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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对于如何在枚举类中放置整数值和字符串，我有一个问题。我使用要存储在数据库中的枚举值。我想要的是这样的public enum MyList {    1,    2,    3,    APPLE,    BANANA}但是值'1‘有个错误，上面写着Syntax error on token "1", Identifie...

问枚举类中的整数和字符串。
EN

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问枚举类中的整数和字符串。EN