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This article mainly introduces the example analysis of life cycle management in Java development platform, which is very detailed and has certain reference value. Friends who are interested must finish it!

First, the traditional method of object life cycle management.

In order to have a deeper understanding of the life cycle management methods in the Java development platform, the author thinks that we need to have an understanding of the traditional life cycle management methods. Because this helps you to have a comparison with each other, you will have a more intuitive impression of the lifecycle management approach in the Java language.

In traditional programming languages, such as C language, the life cycle of objects is considered mainly from the execution efficiency of objects and applications. In order to pursue the execution efficiency of the application, the C language requires that the program developer must determine the storage space and life cycle of the object when writing the application, which can be achieved by stacking or limiting domain variables. If designed in this way, the benefits are obvious. Since the storage space and life cycle of objects are involved in program development, there is no need to spend energy on creating objects while the program is running. What application developers need to know is that creating and freeing storage space for objects in the stack is easy and does not take much time. For example, to create object space in the stack, you only need an assembly instruction to move the top pointer down, and another assembly instruction to move the top pointer up to free storage space. Therefore, the execution speed of the application will be relatively high, and the allocation and release of object storage space can be placed in a position of limited consideration.

But the drawback of this management method is that it is not flexible. Because it is necessary to know the exact number of objects, life cycle, and storage space when developing an application. If you need to re-develop or upgrade the application later, if it involves adding new objects, then the modification will be a lot of work. And for the average application developer, it is difficult to make an accurate prediction of the number and life cycle of objects needed. It can be seen that although this management mode can ensure the running speed of the application, it is also quite limited. It is not only less flexible, but also has higher requirements for application developers.

Second, the method of object life cycle management under Java platform.

Under the Java language platform, it is very different from the traditional object management method. Under the Java language platform, it is called creating objects dynamically. To put it simply, instead of creating objects during application development, objects are dynamically created as needed while the application is running. Unlike the object lifecycle above, dynamically creating objects only considers how many objects need to be created when the application is running, how long their lifecycle is, what the type of object is, and so on. These issues can be finally identified only at the moment the application code is executed. There is no need to pay attention to these issues during application development. For example, in Java language development, there is no need to create objects at first. When you need an object, you can use the new keyword to create an object.

Obviously, because the creation and demise of objects are managed dynamically while the application is running, it is more flexible than traditional static management. When you need a new object phase, you only need to create one in your code using the NEW keyword, without changing anything else. For this reason, languages such as Java, which uses dynamic mechanisms to manage the life cycle of objects, are often considered to be superior to traditional C language programs in upgrading and secondary development. And because objects are created when needed, the requirements for application developers are relatively low. The barriers for application developers to enter the Java language will also be much lower.

But its drawback is that it will affect the execution efficiency of the application. Because if the object is created dynamically, the storage space of the object is dynamically managed while the application is running. So at this point, the application needs to spend extra time allocating storage space in the heap, which is much longer than the time it takes for static management objects to create storage space in the stack. Therefore, under the same conditions, the efficiency of applications developed by Java language is a little lower than that developed by C language. This gap can be large if no other measures are taken to optimize the performance of the Java language.

For this reason, Java language adopts this kind of object life cycle management mode, which mainly focuses on the flexibility in the process of object management. The management way of dynamically creating objects can easily solve the problem of general programming. This will also create some application customization platforms that provide help.

Third, use the garbage collector to automatically collect objects that are not needed.

In addition to the lack of performance, the most important thing is that the dynamic management of objects also has some defects in object recycling. For example, to create an object through the stack (*), the language compiler can determine how long the object lives and automatically recover the space occupied by the object when the time expires. If you create an object on the heap (the second way of object management), the language compiler knows nothing about the life cycle of the application object and when the object will die. For this reason, if you do not take other processors to know, you need to determine the life cycle of the object through the code and reclaim the storage space occupied by the object at the appropriate time. However, this way of judging the life cycle of objects by code will to a large extent cause security vulnerabilities in the application, such as memory leaks and so on.

However, if you use the Java language as the development platform, you don't have to worry about it. Because under the Java language platform, a management mechanism called garbage collector is provided. The garbage collector is like a monitor that monitors the operation of the application all the time. It automatically discovers when the application object dies, thus helping the application free up the space occupied by the object. In other words, if you use the Java language garbage collector, you no longer need to code to determine when the object is dead. If this is done, the Java language compiler will help program developers to do it. To put it bluntly, application developers are only responsible for creating objects. When an object needs to die, it automatically disappears (with the help of the garbage collector, of course).

It can be seen that the deficiency of creating objects through heap can be solved with the help of Java garbage collector. Application developers do not have to worry about when to release the space occupied by the object, and do not need to develop additional code to manage this problem. As a result, the security risks of application memory leakage can be avoided to a certain extent.

Another thing to note is that although the garbage collector of the Java language has solved the problem of object collection and space release. However, it can not play any role in the improvement of performance. So this performance flaw is still a bottleneck resource for the Java language. Of course, this problem can not be solved by us, and language experts are needed to find ways to improve the efficiency of dynamically allocating object space. What we application developers can do is to improve the performance of the application by optimizing the Java language code, code reuse and inheritance and so on.

These are all the contents of the article "sample Analysis of Lifecycle Management in the Java Development platform". Thank you for reading! Hope to share the content to help you, more related knowledge, welcome to follow the industry information channel!

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