简书链接:java单例转kotlin的表现
文章字数：55,阅读全文大约需要1分钟

java代码

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class TestStatic {
    private static final String TAG = "TestStatic";
    private static TestStatic instance;
    private static TestStatic staticField;
    private TestStatic notStaticField;

    public static TestStatic getInstance() {

        if (instance == null) {
            synchronized (TestStatic.class) {
                if (instance == null) {
                    return new TestStatic();
                }
            }
        }

        return instance;
    }

    public TestStatic reflect() {

        try {
            Class<?> aClass = Class.forName(staticField.getClass().getName());
            Field[] declaredFields = aClass.getDeclaredFields();
            for (Field field : declaredFields) {
                field.setAccessible(true);
                System.out.println("FIELD:" + field.getName() + "," + TAG);
            }
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
        return staticField;
    }


    public static void main() {
        TestStatic obj = TestStatic.getInstance();
        TestStatic notStaticField = obj.notStaticField;
        System.out.println("note" + notStaticField);
    }
}

kotlin代码

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internal class TestStatic {
    private val notStaticField: TestStatic? = null

    fun reflect(): TestStatic? {

        try {
            val aClass = Class.forName(staticField!!.javaClass.name)
            val declaredFields = aClass.declaredFields
            for (field in declaredFields) {
                field.isAccessible = true
                println("FIELD:" + field.name + "," + TAG)
            }
        } catch (e: ClassNotFoundException) {
            e.printStackTrace()
        }

        return staticField
    }

    companion object {
        private val TAG = "TestStatic"
        private val instance: TestStatic? = null
        private val staticField: TestStatic? = null

        fun getInstanceXXX(): TestStatic? {

            if (instance == null) {
                synchronized(TestStatic::class.java) {
                    if (instance == null) {
                        return TestStatic()
                    }
                }
            }

            return instance
        }


        fun main() {
            val obj = TestStatic.getInstanceXXX()
            val notStaticField = obj!!.notStaticField
            println("note" + notStaticField!!)
        }
    }
}

//因为getInstance()刚好和默认获取的事例冲突，所以方法名改了下才解决一键转换错误

在其他kotlin文件中的调用

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val obj = TestStatic.getInstanceXXX()
println("hello obj${obj}")

完美