我有一个枚举:
public enum Persons {
CHILD,
PARENT,
GRANDPARENT;
}
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使用ordinal()方法检查枚举成员之间的"层次结构" 是否有任何问题?我的意思是 - 使用它时有什么缺点,不包括冗长,当有人可能在将来意外改变时.
或者做这样的事情会更好:
public enum Persons {
CHILD(0),
PARENT(1),
GRANDPARENT(2);
private Integer hierarchy;
private Persons(final Integer hierarchy) {
this.hierarchy = hierarchy;
}
public Integer getHierarchy() {
return hierarchy;
}
}
Run Code Online (Sandbox Code Playgroud) 呃,我对如何在Java中使用枚举感到困惑.在C#和C++(我通常使用的)中,这似乎没问题,但是Java想要生我的气.>
enum Direction
{
NORTH_WEST = 0x0C,
NORTH = 0x10,
NORTH_EAST = 0x14,
WEST = 0x18,
NONE = 0x20,
EAST = 0x28,
SOUTH_WEST = 0x24,
SOUTH = 0x30,
SOUTH_EAST = 0x3C
}
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有人能告诉我我做错了什么吗?谢谢
以下是错误:
----jGRASP exec: javac -g Test.java
Test.java:79: ',', '}', or ';' expected
NORTH_WEST = 0x0C,
^
Test.java:79: '}' expected
NORTH_WEST = 0x0C,
^
Test.java:80: <identifier> expected
NORTH = 0x10,
^
Test.java:87: ';' expected
SOUTH_EAST = 0x3C
^
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