一個簡單的Android日誌類

Android自帶的日誌類不支持顯示文件名和行號，調試時很不方便。而第三方日誌庫每每又過重。因此本身對Android自帶的日誌類作了一個簡單的封裝，主要是調試時使用，不考慮日誌丟失和性能問題。日誌的輸出以下：

08-12 13:26:25.557 31285 31285 D com.tq.test: [TestFragment.kt:85 com.tq.test.fragment.TestFragment$subscribeUi$5.onChanged] foo bar

用法以下：

// 在Activity或Fragment中
val someValue = "abc";
getLogger().debug(someValue)
getLogger().debug(someValue, x, y, z)
getLogger().error(ex)

// CrashHandler
package com.tq.test

import android.os.Process
import com.tq.test.utility.Logger

class DefaultExceptionHandler(
        private val packageName: String,
        private val next: Thread.UncaughtExceptionHandler? = null
): Thread.UncaughtExceptionHandler {
    
    override fun uncaughtException(thread: Thread, error: Throwable) {
        val logger = Logger.getLogger(packageName)
        logger.error(error, "uncaught exception", thread)

        next?.uncaughtException(thread, error)
        Process.killProcess(Process.myPid())
    }
}

Thread.setDefaultUncaughtExceptionHandler(DefaultExceptionHandler(
        getPackageName(),
        Thread.getDefaultUncaughtExceptionHandler()
))

源代碼以下：

package com.tq.utility

import androidx.appcompat.app.AppCompatActivity
import androidx.fragment.app.Fragment
import android.content.Context
import android.util.Log

class Logger private constructor(val defaultTag: String = "") {

    fun debug(vararg values: Any?) = Log.d(defaultTag, makeMessage(values))
    fun info(vararg values: Any?) = Log.i(defaultTag, makeMessage(values))
    fun warn(vararg values: Any?) = Log.w(defaultTag, makeMessage(values))
    fun error(error: Throwable, vararg values: Any?) = Log.e(defaultTag, makeMessage(values), error)

    private fun makeMessage(values: Array<out Any?>): String {
        // TOOD handle native method
        
        var fileName = "unknown"
        var lineNumber = -1
        var className = "unknown"
        var methodName ="unknown"
        
        val throwable = Throwable()
        val stacks = throwable.getStackTrace()
        val depth = 2
        if (stacks.size > depth) {
            val stack = stacks[depth]
            fileName = stack.getFileName()
            lineNumber = stack.getLineNumber()
            className = stack.getClassName()
            methodName = stack.getMethodName()
        }

        val valueString = values.map{ it?.toString() ?: "null" }.joinToString()
        return "[$fileName:$lineNumber $className.$methodName] $valueString"
    }

    companion object {
        fun getLogger(tag: String): Logger {
            return Logger(tag)
        }

        fun getLogger(context: Context) = getLogger(context.getPackageName())
    }
}

fun AppCompatActivity.getLogger() = Logger.Companion.getLogger(this)
fun Fragment.getLogger() = Logger.Companion.getLogger(activity!!)