根据传入的字符串设置枚举值

I have a number of setter methods which take an enum. These are based on incoming objects attribute. Rather than write a bunch of these is there a way around having to hard code say 10 different case statements. Would there be a way to create a reusable method?

我有一些设置枚举的setter方法。它们基于传入对象属性。与其写一堆这样的东西，还不如用硬编码，比如10个不同的case语句。是否有方法创建可重用的方法?

//Side class declared as
public final enum Side

//How I initialise side
static Side side = Side.SELL;//default

//method to set object
Obj.setSide(sideEnum(zasAlloc.getM_buySellCode()));

//How I am implementing it
    public static Side sideEnum(String buysell)
    {

        if(buysell.equalsIgnoreCase("S"))
        {
            side = Side.SELL; //default 
        }
        else if(buysell.equalsIgnoreCase("B"))
        {
            side = Side.BUY; 
        }

        return side;

    }

4 个解决方案

#1

You can implement that functionality in your Enum.

您可以在Enum中实现该功能。

public enum Side {

    BUY("B"), SELL("S"), ...

    private String letter;
    private Side(String letter) {
        this.letter = letter;
    }

    public static Side fromLetter(String letter) {
        for (side s : values() ){
            if (s.letter.equals(letter)) return s;
        }
        return null;
    }

}

You could also do this as a helper static method if you can't edit Side.

如果不能编辑边，也可以将其作为助手静态方法。

public static Side fromString(String from) {
    for (Side s: Side.values()) {
        if (s.toString().startsWith(from)) {
            return s;
        }
    }

    throw new IllegalArgumentException( from );
}

The above method assumes your strings correspond to the names of you enums.

上面的方法假设您的字符串对应于您的枚举名。

#2

Enums have valueOf() method that can be used to convert from String. Is it what you are looking for?

枚举具有valueOf()方法，可用于从字符串转换。这就是你要找的吗?

#3

I ended up using a simple object map:

最后我使用了一个简单的对象映射:

private static HashMap<String, Side> sideMap = new HashMap<String, Side>(7);
static{
    sideMap.put("B", Side.BUY);
    sideMap.put("S", Side.SELL);
}

and simply using

并简单地使用

Obj.setSide(sideMap.get(zasAlloc.getM_buySellCode()));

#4

I think you need smth like:

我认为你需要像:

Obj.setSide(Side.valueOf(zasAlloc.getM_buySellCode()));

#1