Java如何定义枚举行为方法

public enum Operation {
    ADD("+") {
        public int apply(int a, int b) {
            return a + b;
        }
    },
    SUBTRACT("-") {
        public int apply(int a, int b) {
            return a - b;
        }
    },
    MULTIPLY("*") {
        public int apply(int a, int b) {
            return a * b;
        }
    },
    DIVIDE("/") {
        public int apply(int a, int b) {
            return b != 0 ? a / b : 0;
        }
    };
<pre class="brush:java;toolbar:false;">private final String symbol;

Operation(String symbol) {
    this.symbol = symbol;
}

public abstract int apply(int a, int b);

@Override
public String toString() {
    return "Operation{" + "symbol='" + symbol + '\'' + '}';
}

}

public enum Logger {
    DEBUG {
        void log(String message) {
            System.out.println("[DEBUG] " + message);
        }
    },
    INFO {
        void log(String message) {
            System.out.println("[INFO] " + message);
        }
    },
    ERROR {
        void log(String message) {
            System.err.println("[ERROR] " + message);
        }
    };
<pre class="brush:java;toolbar:false;">abstract void log(String message);

}

// 使用示例 Logger.DEBUG.log("程序开始运行");

interface Task {
    void execute();
}
<p>public enum Job implements Task {
IMPORT_DATA {
public void execute() {
System.out.println("正在导入数据...");
}
},
EXPORT_REPORT {
public void execute() {
System.out.println("正在生成报告...");
}
};</p><pre class="brush:java;toolbar:false;">// 可添加通用辅助方法
public void run() {
    System.out.print("任务开始: ");
    execute();
}

}