打印代码块执行时间方案，优雅打印执行耗时日志

蔚落 2023-01-07 03:53 181阅读 0赞

**目的：打印代码块的执行时间**

**做法：定义工具类 实现 AutoCloseable，重写close方法。初始化时记录开始时间，代码块结束时执行close方法计算时长并打印日志**

**实现：通过字符串占位符，实现其他日志传入。并且通过重载构建函数，支持传入自定义日志消息，可以将时间打印在日志前面和后面**

**完整代码如下：(使用方式看 main 方法)**

package com.example.demo.utils;
    
    import lombok.extern.slf4j.Slf4j;
    
    /**
     * 统计代码块执行时间
     * 使用方式看 main 函数
     *
     * @Author XZ.Tan
     * @Date: 2021/1/15 10:44
     * @Version 1.0
     */
    @Slf4j
    public class CountRunTimeCostUtil implements AutoCloseable {
    
        /**
         * 开始执行时间
         */
        private long startTime;
    
        /**
         * 日志
         */
        private String msg;
    
        /**
         * 时间是否打印在日志开始
         */
        private boolean isStart;
    
        /**
         * 默认耗时加在日志末尾
         *
         * @param msg
         */
        public CountRunTimeCostUtil(String msg, Object... args) {
            String parse = parse(msg, args);
            this.startTime = System.currentTimeMillis();
            this.msg = parse;
            this.isStart = false;
        }
    
        /**
         * 
         *
         * @param msg
         * @param isStart
         */
        public CountRunTimeCostUtil(Boolean isStart, String msg, Object... args) {
            String parse = parse(msg, args);
            this.startTime = System.currentTimeMillis();
            this.msg = parse;
            if (isStart) {
                this.isStart = true;
            } else {
                this.isStart = false;
            }
        }
    
        @Override
        public void close() {
            if (isStart) {
                log.info("执行耗时：{}ms, {}", System.currentTimeMillis() - startTime, msg);
            } else {
                log.info("{}, 执行耗时：{}ms", msg, System.currentTimeMillis() - startTime);
            }
        }
    
        /**
         * 将字符串text中由openToken和closeToken组成的占位符依次替换为args数组中的值
         *
         * @param openToken
         * @param closeToken
         * @param text
         * @param args
         * @return
         */
        public static String parse(String openToken, String closeToken, String text, Object... args) {
            if (args == null || args.length <= 0) {
                return text;
            }
            int argsIndex = 0;
    
            if (text == null || text.isEmpty()) {
                return "";
            }
            char[] src = text.toCharArray();
            int offset = 0;
            // search open token
            int start = text.indexOf(openToken, offset);
            if (start == -1) {
                return text;
            }
            final StringBuilder builder = new StringBuilder();
            StringBuilder expression = null;
            while (start > -1) {
                if (start > 0 && src[start - 1] == '\\') {
                    // this open token is escaped. remove the backslash and continue.
                    builder.append(src, offset, start - offset - 1).append(openToken);
                    offset = start + openToken.length();
                } else {
                    // found open token. let's search close token.
                    if (expression == null) {
                        expression = new StringBuilder();
                    } else {
                        expression.setLength(0);
                    }
                    builder.append(src, offset, start - offset);
                    offset = start + openToken.length();
                    int end = text.indexOf(closeToken, offset);
                    while (end > -1) {
                        if (end > offset && src[end - 1] == '\\') {
                            // this close token is escaped. remove the backslash and continue.
                            expression.append(src, offset, end - offset - 1).append(closeToken);
                            offset = end + closeToken.length();
                            end = text.indexOf(closeToken, offset);
                        } else {
                            expression.append(src, offset, end - offset);
                            offset = end + closeToken.length();
                            break;
                        }
                    }
                    if (end == -1) {
                        // close token was not found.
                        builder.append(src, start, src.length - start);
                        offset = src.length;
                    } else {
                        ///仅仅修改了该else分支下的个别行代码
    
                        String value = (argsIndex <= args.length - 1) ?
                                (args[argsIndex] == null ? "" : args[argsIndex].toString()) : expression.toString();
                        builder.append(value);
                        offset = end + closeToken.length();
                        argsIndex++;
                        
                    }
                }
                start = text.indexOf(openToken, offset);
            }
            if (offset < src.length) {
                builder.append(src, offset, src.length - offset);
            }
            return builder.toString();
        }
    
        /**
         * 占位符替换
         *
         * @param text
         * @param args
         * @return
         */
        public static String parse(String text, Object... args) {
            return parse("{", "}", text, args);
        }
    
        /**
         * 如何使用
         *
         * @param args
         */
        public static void main(String[] args) {
    
            // 耗时
    //        try (CountRunTimeCostUtil c = new CountRunTimeCostUtil("{} aabb", "耗时测试")) {
            try (CountRunTimeCostUtil c = new CountRunTimeCostUtil("耗时测试")) {
    //        try (CountRunTimeCostUtil c = new CountRunTimeCostUtil(true,"{} aabb", "耗时测试")) {
    //        try (CountRunTimeCostUtil c = new CountRunTimeCostUtil(false,"耗时测试")) {
                // 业务代码块 start
                try {
                    Thread.sleep(2000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                // 业务代码块 start
            }
        }
    }