java的析构函数,是否有Java的析构函数？

最新推荐文章于 2025-01-16 20:23:59 发布

转载最新推荐文章于 2025-01-16 20:23:59 发布 · 175 阅读

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由于Java是垃圾回收语言，没有直接的析构函数。通常通过定义`close`方法来实现资源清理，并在`finalize`中进行最后的检查和错误记录。当需要重置应用时，调用`close`方法释放资源，避免内存泄漏。如果用户频繁操作并按下重置按钮，依赖垃圾收集可能导致延迟释放，但Java提供了机制来优雅地处理这种情况。

Is there a destructor for Java? I don't seem to be able to find any documentation on this. If there isn't, how can I achieve the same effect?

To make my question more specific, I am writing an application that deals with data and the specification say that there should be a 'reset' button that brings the application back to its original just launched state. However, all data have to be 'live' unless the application is closed or reset button is pressed.

Being usually a C/C++ programmer, I thought this would be trivial to implement. (And hence I planned to implement it last.) I structured my program such that all the 'reset-able' objects would be in the same class so that I can just destroy all 'live' objects when a reset button is pressed.

I was thinking if all I did was just to dereference the data and wait for the garbage collector to collect them, wouldn't there be a memory leak if my user repeatedly entered data and pressed the reset button? I was also thinking since Java is quite mature as a language, there should be a way to prevent this from happening or gracefully tackle this.

解决方案

Because Java is a garbage collected language you cannot predict when (or even if) an object will be destroyed. Hence there is no direct equivalent of a destructor.

There is an inherited method called finalize, but this is called entirely at the discretion of the garbage collector. So for classes that need to explicitly tidy up, the convention is to define a close method and use finalize only for sanity checking (i.e. if close has not been called do it now and log an error).

There was a question that spawned in-depth discussion of finalize recently, so that should provide more depth if required...