使用字符串代替变量名称 [英] Use string in place of variable name

问题描述

如果您有一个名为xyz的Java变量。
然后我定义一个字符串，其中包含我想要使用的命名变量的值。

If you have a Java variable named xyz. Then later on I define a string which has the value of the named variable I want to play with.

String x="xyz";

如何让Java将String x识别为变量xyz的指针？

How do I get Java to recognise that String x as a pointer to variable xyz?

一个任意的例子：

JButton a= new JButton();

稍后......

String x="a";

我现在要说的是

JButton called string x.setPreferredSize(new Dimension(40,30));

推荐答案

一般来说，如果你想访问一个变量这样，你必须使用反射，这是较慢且有潜在危险。

In general, if you want to access a variable in this way, you have to use Reflection, which is slower and potentially dangerous.

但是，由于你有一个非常具体的场景，我会采取不同的方法。为什么不把你的按钮或其他元素放到地图中，键是字符串：

However, since you have a very specific scenario in mind, I'd take a different approach. Why not put your buttons or other elements into a map, with keys that are strings:

Map<String, JComponent> currentComponents = new HashMap<String, JComponent>();

currentComponents.put("a", new JButton());

String x = "a";

currentComponents.get(x).setPreferredSize(new Dimension(40,30));

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