Heavy object for more sensitive memory leaking detection

HeavyObject.kt

package io.github.dector.tools

import android.util.Log
import java.lang.ref.WeakReference


/**
 * Usage example: `class Foo : HeavyObject by HeavyObject.new() {`.
 */
interface HeavyObject {

    companion object {

        fun new(sizeBytes: Int = 1024 * 1024 * 50, debug: Boolean = true): HeavyObject =
            HeavyObjectImpl(sizeBytes, debug)
    }
}

private class HeavyObjectImpl(sizeBytes: Int, debug: Boolean) : HeavyObject {

    private val TAG = "HeavyObject #${(this as Any).hashCode().toString(16)}"

    init {
        if (debug) {
            log(TAG, "Allocating $sizeBytes bytes")
            filterInstance()
            log(TAG, "Before allocation can see ${instances.size} instances")
        }
    }

    @Suppress("unused")
    private val load = ByteArray(sizeBytes) { 1 }

    init {
        if (debug) {
            instances.add(WeakReference(this))
            log(TAG, "After allocation can see ${instances.size} instances")
        }
    }

    private fun filterInstance() {
        instances.removeAll { it.get() == null }
    }

    companion object {
        private val instances = mutableListOf<WeakReference<HeavyObject>>()
    }
}

@Suppress("NOTHING_TO_INLINE")
private inline fun log(tag: String, message: String) {
    Log.w(tag, message)
}