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Java enum 数据类型以语言支持的方式创建和使用常量值。通过定义一组有限的值，enum 变得比 int 或 string 等常量变量更安全。

本教程演示了如何在 Java 中使用自定义变量创建 enum。

在 Java 中为枚举分配自定义值

让我们将自定义值附加到枚举并尝试获取和打印它们。下面的示例创建了具有相应用法的不同编程语言的枚举。

package delftstack;

enum Programming_Usage {
  // enum constructor calling with one custom string value
  PYTHON("DataScience"),
  PHP("WebDevelopment"),
  JAVA("AndroidDevelopment"),
  MATLAB("ImageProcessing");

  // declare the private string to get values later
  private String usage;

  // get usage of programming language method
  public String get_usage() {
    return this.usage;
  }

  // enum constructor
  private Programming_Usage(String usage) {
    this.usage = usage;
  }
}

public class Enum_Value {
  public static void main(String args[]) {
    // This example will print usage with corresponding programming language.
    Programming_Usage[] usages = Programming_Usage.values();

    for (Programming_Usage usage : usages) {
      // use get usage method method to get the values of usage and programming language
      System.out.println(
          "For " + usage.get_usage() + ", we mostly use " + usage.name() + " programming");
    }
  }
}

上面的代码将获取枚举的自定义值并打印具有相应用法的编程语言，其中 name() 是枚举的内置方法，get_usage() 是我们定义的方法。

输出：

For DataScience, we mostly use PYTHON programming
For WebDevelopment, we mostly use PHP programming
For AndroidDevelopment, we mostly use JAVA programming
For ImageProcessing, we mostly use MATLAB programming