统计代码执行时间

RunTimer.java

import java.util.ArrayList;


public class RunTimer {
    public static void main(String[] args) {
        RunTimer timer = new RunTimer("Tag");
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        timer.addSplit("休眠一秒后");
        try {
            Thread.sleep(2000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        timer.addSplit("休眠两秒后");
        timer.dumpToLog();
    }

    private String mTag;

    private ArrayList<Long> mSplits;

    private ArrayList<String> mSplitLabels;

    public RunTimer(String tag) {
        reset(tag);
    }

    public void reset(String tag) {
        mTag = tag;
        reset();
    }

    public void reset() {
        if (mSplits == null) {
            mSplits = new ArrayList<>();
            mSplitLabels = new ArrayList<>();
        } else {
            mSplits.clear();
            mSplitLabels.clear();
        }
        addSplit(null);
    }

    public void addSplit(String splitLabel) {
        long now = System.currentTimeMillis();
        mSplits.add(now);
        mSplitLabels.add(splitLabel);
    }

    public void dumpToLog() {
        System.out.println(mTag + ":\t" + "开始计时");
        final long first = mSplits.get(0);
        long now = first;
        for (int i = 1; i < mSplits.size(); i++) {
            now = mSplits.get(i);
            final String splitLabel = mSplitLabels.get(i);
            final long prev = mSplits.get(i - 1);
            System.out.printf("%s:\t%s耗时:\t%d ms \n", mTag, splitLabel, now - prev);
        }
        System.out.println(mTag + ":\t" + "总计耗时:\t" + (now - first) + " ms");
    }
}