收藏。排序比较方法违反了它的一般约定

Question

首先，很抱歉再次就这个话题提问。我很清楚这里有很多问题和答案。我已经读了其中的一些，但我的问题是我仍然不知道我做错了什么。这是我的代码：

Collections.sort(hLines, new Comparator<Line>() {

        @Override
        public int compare(Line lhs, Line rhs) {
            if ( lhs.p1.y < rhs.p1.y){
                if (lhs.p2.y < rhs.p2.y)
                    return 1;
                else
                    return -1;
            }
            if (lhs.p1.y > rhs.p1.y){
                if (lhs.p2.y > rhs.p2.y)
                    return -1;
                else
                    return 1;
            }
            else
                return 0;
        }

    });
    Collections.sort(vLines, new Comparator<Line>() {

        @Override
        public int compare(Line lhs, Line rhs) {
            if ( lhs.p1.x < rhs.p1.x){
                if (lhs.p2.x < rhs.p2.x)
                    return 1;
                else
                    return -1;
            }
            if (lhs.p1.x > rhs.p1.x){
                if (lhs.p2.x > rhs.p2.x)
                    return -1;
                else
                    return 1;
            }
            else
            return 0;
        }

    });

看来我只是瞎了眼，看不到我的错误，所以如果你们中有人能帮我解决这个问题，我将非常感谢。

编辑:我想做的是确定一条线在左上角有0/0坐标的坐标系中是上、下、最左还是最右。这些点是double类型的。下面是错误消息:

06-03 10:42:22.576: E/OpenCV_NativeCamera(15810): CameraHandler::Notify: msgType=4 ext1=0 ext2=0
06-03 10:42:22.815: E/OpenCV_NativeCamera(15810): CameraHandler::Notify: msgType=4 ext1=1 ext2=0
06-03 10:42:22.848: E/OpenCV_NativeCamera(15810): CameraHandler::Notify: msgType=4 ext1=1 ext2=0
06-03 10:42:26.408: E/OpenCV_NativeCamera(15810): CameraHandler::Notify: msgType=4 ext1=0 ext2=0
06-03 10:42:26.747: E/OpenCV_NativeCamera(15810): CameraHandler::Notify: msgType=4 ext1=1 ext2=0
06-03 10:42:26.781: E/OpenCV_NativeCamera(15810): CameraHandler::Notify: msgType=4 ext1=1 ext2=0
06-03 10:42:29.474: E/OpenCV_NativeCamera(15810): CameraHandler::Notify: msgType=4 ext1=0 ext2=0
06-03 10:42:30.613: E/OpenCV_NativeCamera(15810): CameraHandler::Notify: msgType=4 ext1=0 ext2=0
06-03 10:42:30.646: E/OpenCV_NativeCamera(15810): CameraHandler::Notify: msgType=4 ext1=0 ext2=0
06-03 10:42:30.874: E/AndroidRuntime(15810): FATAL EXCEPTION: Thread-2592
06-03 10:42:30.874: E/AndroidRuntime(15810): java.lang.IllegalArgumentException: Comparison method violates its general contract!
06-03 10:42:30.874: E/AndroidRuntime(15810):    at java.util.TimSort.mergeHi(TimSort.java:864)
06-03 10:42:30.874: E/AndroidRuntime(15810):    at java.util.TimSort.mergeAt(TimSort.java:481)
06-03 10:42:30.874: E/AndroidRuntime(15810):    at java.util.TimSort.mergeForceCollapse(TimSort.java:422)
06-03 10:42:30.874: E/AndroidRuntime(15810):    at java.util.TimSort.sort(TimSort.java:219)
06-03 10:42:30.874: E/AndroidRuntime(15810):    at java.util.TimSort.sort(TimSort.java:169)
06-03 10:42:30.874: E/AndroidRuntime(15810):    at java.util.Arrays.sort(Arrays.java:2038)
06-03 10:42:30.874: E/AndroidRuntime(15810):    at java.util.Collections.sort(Collections.java:1891)
06-03 10:42:30.874: E/AndroidRuntime(15810):    at com.example.camera.RectangleDetector.drawLines(RectangleDetector.java:108)
06-03 10:42:30.874: E/AndroidRuntime(15810):    at com.example.camera.RectangleDetector.findRectangle(RectangleDetector.java:94)
06-03 10:42:30.874: E/AndroidRuntime(15810):    at com.example.camera.MainActivity.onCameraFrame(MainActivity.java:114)
06-03 10:42:30.874: E/AndroidRuntime(15810):    at org.opencv.android.CameraBridgeViewBase.deliverAndDrawFrame(CameraBridgeViewBase.java:387)
06-03 10:42:30.874: E/AndroidRuntime(15810):    at org.opencv.android.NativeCameraView$CameraWorker.run(NativeCameraView.java:177)
06-03 10:42:30.874: E/AndroidRuntime(15810):    at java.lang.Thread.run(Thread.java:838)

Answer 1

这不是一个正确的顺序。

考虑第一种方法：

如果第一个(左)点的y坐标小于第二个(右)点的y坐标，则返回1，否则返回-1。

这意味着如果你比较一个y坐标为4和6的点和一个y坐标为6和4的点，你将返回-1，不管哪个点是第一个参数，这相当于说点1 "

您的< code>compare方法应该处理lhs.p1.y和rhs.p1.y ()关系的每个组合