用于验证 java.lang.IllegalArgumentException: Comparison method violates its general contract! 的测试用例

comparable-contract-test.kt

package com.tencent.tip.bitmapprofiler.extension

import org.junit.Test
import java.lang.ref.WeakReference
import java.util.*
import kotlin.collections.ArrayList

class ContractTest {

    @Test
    fun testContract() {
        while (true) {
            runTest()
        }
    }

    private fun runTest() {
        val n = 500000
        val rand = Random()
        val list = ArrayList<MockBitmapTrace>()
        for (i in 0..n) {
            list.add(MockBitmapTrace(Bmp(rand.nextInt())))
        }
        list.filter { it.isBitmapAlive() }
                //.sortedBy { it.currentBitmapSize() }
                .sortedBy { it.oldBitmapSize() }
                .reversed()
    }

}

private class MockBitmapTrace(referent: Bmp) : WeakReference<Bmp>(referent) {

    private val allocationByteCount: Int = 0

    fun isBitmapAlive() = get() != null
    fun currentBitmapSize(): Int = get()?.allocationByteCount ?: 0
    fun oldBitmapSize(): Int = allocationByteCount

}

data class Bmp(var allocationByteCount: Int)