一个简单的Android SharedPreferences存储工具类

话不多说，直接上代码：

/**
 * SP工具类
 * */

class SharedPreferenceUtil private constructor(context: Context) {

    private val preferences: SharedPreferences by lazy {
        context.getSharedPreferences(fileName?: DEFAULT_FILE_NAME, Context.MODE_PRIVATE)
    }
    private val editor: SharedPreferences.Editor by lazy { preferences.edit() }

    companion object {
        private const val DEFAULT_FILE_NAME = "coin_prefs"
        private var instance: SharedPreferenceUtil? = null
        private var fileName: String? = null

        @Synchronized
        fun getInstance(context: Context): SharedPreferenceUtil? {
            if (instance == null) {
                instance = SharedPreferenceUtil(context)
            }
            return instance
        }

        @Synchronized
        fun getInstance(context: Context, customFileName: String): SharedPreferenceUtil? {
            fileName = customFileName
            if (instance == null) {
                instance = SharedPreferenceUtil(context)
            }
            return instance
        }
    }

    fun putString(key: String, value: String) {
        editor.putString(key, value).apply()
    }

    fun putBoolean(key: String, value: Boolean) {
        editor.putBoolean(key, value).apply()
    }

    fun putFloat(key: String, value: Float) {
        editor.putFloat(key, value).apply()
    }

    fun putInt(key: String, value: Int) {
        editor.putInt(key, value).apply()
    }

    fun putLong(key: String, value: Long) {
        editor.putLong(key, value).apply()
    }

    fun clear() {
        editor.clear().apply()
    }

    fun remove(key: String) {
        editor.remove(key).apply()
    }

    fun getString(key: String, defValue: String): String? {
        return preferences.getString(key, defValue)
    }

    fun getBoolean(key: String, defValue: Boolean): Boolean {
        return preferences.getBoolean(key, defValue)
    }

    fun getFloat(key: String, defValue: Float): Float {
        return preferences.getFloat(key, defValue)
    }

    fun getInt(key: String, defValue: Int): Int {
        return preferences.getInt(key, defValue)
    }

    fun getLong(key: String, defValue: Long): Long {
        return preferences.getLong(key, defValue)
    }

    fun contains(key: String): Boolean {
        return preferences.contains(key)
    }
}

小tips：如果数据读写不频繁，例如在冷启动阶段读一下开关配置等，完全可以用sp，但是读写频繁，或者数据量大，建议还是找一下更优解，毕竟SharedPreferences的底层实现为读写XML文件，并且每次读写都会创建一个新的Editor，这就使得其加载文件和解析文件的性能损耗巨大，另外跨进程也不是它的强项。