Arrays.sort实现原理

2021/7/20 23:20:25

本文主要是介绍Arrays.sort实现原理,对大家解决编程问题具有一定的参考价值,需要的程序猿们随着小编来一起学习吧!

Collections.sort方法底层就是调用的array.sort方法

比较器的方式

 

TimSort

 

static void sort(Object[] a, int lo, int hi, Object[] work, int workBase, int workLen) {
    assert a != null && lo >= 0 && lo <= hi && hi <= a.length;

    int nRemaining  = hi - lo;
    if (nRemaining < 2)
        return;  // Arrays of size 0 and 1 are always sorted

    // If array is small, do a "mini-TimSort" with no merges
    if (nRemaining < MIN_MERGE) {
        int initRunLen = countRunAndMakeAscending(a, lo, hi);
        binarySort(a, lo, hi, lo + initRunLen);
        return;
    }
    ComparableTimSort ts = new ComparableTimSort(a, work, workBase, workLen);
    int minRun = minRunLength(nRemaining);
    do {
        // Identify next run
        int runLen = countRunAndMakeAscending(a, lo, hi);

        // If run is short, extend to min(minRun, nRemaining)
        if (runLen < minRun) {
            int force = nRemaining <= minRun ? nRemaining : minRun;
            binarySort(a, lo, lo + force, lo + runLen);
            runLen = force;
        }

        // Push run onto pending-run stack, and maybe merge
        ts.pushRun(lo, runLen);
        ts.mergeCollapse();

        // Advance to find next run
        lo += runLen;
        nRemaining -= runLen;
    } while (nRemaining != 0);

    // Merge all remaining runs to complete sort
    assert lo == hi;
    ts.mergeForceCollapse();
    assert ts.stackSize == 1;
}

 Collections.sort方法或者是Arrays.sort方法,底层实现都是TimSort实现的

TimSort算法就是找到已经排好序数据的子序列,然后对剩余部分排序,然后合并起来



这篇关于Arrays.sort实现原理的文章就介绍到这儿,希望我们推荐的文章对大家有所帮助,也希望大家多多支持为之网!


扫一扫关注最新编程教程