how to find memory leaks in java

Android development often uses Handler, but we find that every use of Handler appears: This Handler class should be static or leaks might occur (null). Android Lint is intended to prompt us, so using handler can easily cause memory leaks. But you will find it useless to change to static. Because it doesn't solve the problem at all.First, we have to confirm why th

window toolbar (Update Heap),(4) Click the Cause GC button on the right window to get the heap information of the current program.Similarly, as the program runs, multiple clicks to get the heap size, if only increase, it also indicates that your program has a memory leak.3. ADB command to view memory informationIn fact, the most comprehensive and simplest way is to use the ADB command to view the

some phenomena before the system crashes Each time the garbage collection is growing longer, from the previous 10ms extended to about 50ms, FULLGC time also has before the 0.5s extended to 4, 5sFULLGC more and more times, the most frequent interval less than 1 minutes to carry out a FULLGC. Older generations have larger memory and no memory is released after each FULLGC, and the system will not be able to

In recent days, I've seen some articles about JavaScript memory management, which is simpler than the Java JVM's memory management.In the process of learning, found that many netizens talked about circular references, saying that circular references will cause memory leaks,

.5. Single-Case modeImproper use of singleton mode is a common problem that causes memory leaks, where a singleton object will exist in the JVM's lifetime (in the form of a static variable) after it is initialized, and if the Singleton object holds a reference to an external object, the external object will not be properly reclaimed by the JVM, causing a memory l

=mhandler.obtainmessage (); Mhandler.sendmessage (msg); }}). Start ();}Private Static class copyfilehandler extends Handler {Weakreference Public Copyfilehandler(appstartactivity activity) {mactivity =NewWeakreference Public void Handlemessage(Message msg) {FinalAppstartactivity activity = Mactivity.get ();//handle you message here!}}Why are memory leaksSo why not do this will cause a memory leak?Th

In the previously published article "How to use the *stats and *PROFILE/PGM features of the performance detectors", I explained the *stats and *profile data collection types of the performance detectors, which can be very handy for data collection, And it's easy to analyze where the CPU time is being used. In this article, I'll switch the angle to focus on the memory leak problem. Memory

Web services are always inexplicably run after a period of time after the JVM directly outofmemory error, memory leak problem is not easy to find, this article on some of the basic knowledge to find memory leaks to do a summary, does not involve a specific case analysis. 1 JVM Memory Exception data shows an example of

One of the most common cases of memory leaks in Android is the long-term retention of references to context, especially activity, so that activity cannot be destroyed. This also means that all the member variables in the activity are not destroyed. This article only describes how to avoid this situation, others such as bitmap not timely recovery caused by the oom exception is not discussed temporarily.First

When using handler to update the UI, I wrote this:publicclass SampleActivity extends Activity { privatefinalnew Handler() { @Override publicvoidhandleMessage(Message msg) { // TODO } }}It looks normal, but Android Lint gives a warning:This Handler class should is static or leaks might occurThis means: This handler must be static, otherwise it will cause a memory leak.In fact, for this proble

This article, the main solution to the doubts: 1. The weak references mentioned in Threadlocal.threadlocalmap, will the weak references be recycled? 2. What is the case for weak reference recycling?3. Java threadlocal and under what circumstances will the memory leak? With these questions, I simulated the structure of the Threadlocal.threadlocalmap, first show the structure of their own: the realization of

This article is translated by ImportNew- suo yuan from captaindebugImportNew. Note: if you are interested in Java technology translation, join our Java Development Team. For more information about how to participate, see group introduction. If you have read the first part of this blog, you will know that the sample code for Memory leakage is used to create a simu

memory leaks are implicit references (implicit reference) and Explicit references (explicit reference).WorkaroundThe method of resolving implicit references is simple, as long as you use an internal non-static class (Non-static inner Class) or top-level class(a variable defined in a separate Java file) to make implicit explicit, thus avoiding

What is a memory leak?Any programming language that needs to be used in memory at run time, e.g. in a function, var arr = [1, 2, 3, 4, 5]; For such an array, memory is required.However, after using these memory, if they are not used again, but are not released in time, this is called

instances, why there are 418 so many;And so on, the dot button, Run GC, and total 5 increments per point, proves that the point class is not recoverable;Already integrated into Eclipse, can profile as Java application, very convenient;So why didn't the point class release? Clearly it is useless;The actual project, find source code and then find the reference will be exhausted people, we still through the runtime stack snapshot to see it;Switch to the

Http://www.androiddesignpatterns.com/2013/01/inner-class-handler-memory-leak.htmlConsider the following code: 123456789 TD class= "Code" > public class sampleactivity extends activity {private Final handler mleakyhandler = new () { @Override public handlemessage (message msg) {//... } } /span> While not readily obvious, this code can cause cause a massive