Java获取自身被调用点

1. 场景

打印日志的时候，需要获取是在哪个地方被调用了，把调用点的信息一并打印出来。

2. 获取自身被调用点的方法

可以通过获取线程的调用栈，遍历后找到调用点。

3. 代码实现

import java.text.SimpleDateFormat;
import java.util.Date;

public class Log {
    private static final String INFO = "INFO";
    private static final String WARN = "WARN";
    private static final String ERROR = "ERROR";
    private static final String DEBUG = "DEBUG";
    private static final String THREAD_CLASS_NAME = Thread.class.getName();
    private static final String SELF_CLASS_NAME = Log.class.getName();
    private static final SimpleDateFormat DATE_FORMAT = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");

    private static StackTraceElement findCallPoint() {
        Thread currentThread = Thread.currentThread();
        StackTraceElement[] stackTraces = currentThread.getStackTrace();
        for (StackTraceElement stackTrace : stackTraces) {
            if (THREAD_CLASS_NAME.equals(stackTrace.getClassName()) || SELF_CLASS_NAME.equals(stackTrace.getClassName())) {
                continue;
            }
            return stackTrace;
        }
        return null;
    }

    private static String getMsgPrefix(String msgType) {
        StackTraceElement callPoint = findCallPoint();
        if (callPoint == null) {
            return "-";
        }
        return String.format("%s  %s --- %s(%d)  \t%s()\t", DATE_FORMAT.format(new Date()), msgType,
                callPoint.getClassName(), callPoint.getLineNumber(), callPoint.getMethodName());
    }

    public static void info(String msg) {
        System.out.println(getMsgPrefix(INFO) + msg);
    }

    public static void warn(String msg) {
        System.out.println(getMsgPrefix(WARN) + msg);
    }

    public static void error(String msg) {
        System.out.println(getMsgPrefix(ERROR) + msg);
    }

    public static void debug(String msg) {
        System.out.println(getMsgPrefix(DEBUG) + msg);
    }
}

4. 测试

测试代码：

package com.example.study.controller;

public class Test {
    public static void main(String[] args) {
        Log.info("=====testLog main=====");
        testLog();
    }

    private static void testLog() {
        Log.info("=====testLog info=====");
        Log.warn("=====testLog warn=====");
        Log.error("=====testLog error=====");
        Log.debug("=====testLog debug=====");
    }
}

控制台输出：

2024-12-26 23:18:35.313  INFO --- com.example.study.controller.Test(7)  	main()	=====testLog main=====
2024-12-26 23:18:35.315  INFO --- com.example.study.controller.Test(12)  	testLog()	=====testLog info=====
2024-12-26 23:18:35.315  WARN --- com.example.study.controller.Test(13)  	testLog()	=====testLog warn=====
2024-12-26 23:18:35.315  ERROR --- com.example.study.controller.Test(14)  	testLog()	=====testLog error=====
2024-12-26 23:18:35.315  DEBUG --- com.example.study.controller.Test(15)  	testLog()	=====testLog debug=====