heap

问题 We are writing a java program which keeps a password in memory. Unfortunately, the user can easily use jconsole or jmap to create a heap dump file and open it to find the password. I think jconsole connects jvm using local sockets. I wanna know, is there any way to disable jmx even for local users? Is there any way to totally disable heap dumps? As the user have access to the memory segment, this is possible to access the password anyway. However, I wanna disable standards ways of doing that

问题 Is a "static final" directly allocated into young gen or old gen or perm gen? (I guess it will most likely land into old gen over the time I suppose.) If it is allocated in the perm gen then, will it be garbage collected when class unloading takes place in Perm Gen ? 回答1: Is a "static final" directly allocated into young gen or old gen or perm gen? An object referenced by a static final variable will be allocated according to the same rules as any other object. It is most likely to be

问题 I've installed Android Studio 1.1.0. I haven't done anything yet like start new Android application or import anything. Somehow it is trying to build something and it throws sync error. Error:Unable to start the daemon process. This problem might be caused by incorrect configuration of the daemon. For example, an unrecognized jvm option is used. Please refer to the user guide chapter on the daemon at http://gradle.org/docs/2.2.1/userguide/gradle_daemon.html Please read the following process

问题 I've installed Android Studio 1.1.0. I haven't done anything yet like start new Android application or import anything. Somehow it is trying to build something and it throws sync error. Error:Unable to start the daemon process. This problem might be caused by incorrect configuration of the daemon. For example, an unrecognized jvm option is used. Please refer to the user guide chapter on the daemon at http://gradle.org/docs/2.2.1/userguide/gradle_daemon.html Please read the following process

问题 I've installed Android Studio 1.1.0. I haven't done anything yet like start new Android application or import anything. Somehow it is trying to build something and it throws sync error. Error:Unable to start the daemon process. This problem might be caused by incorrect configuration of the daemon. For example, an unrecognized jvm option is used. Please refer to the user guide chapter on the daemon at http://gradle.org/docs/2.2.1/userguide/gradle_daemon.html Please read the following process

问题 Finished implementing the minimal Heap structure with awesome help from Micheal . Right now I have one thing missing so it dynamically grows. As you can see in this image, it isn't dynamic: Instead of having a fixed size when I do pmm_map_physical_virtual(0x800000,0xC0800000) , the max I can go to is 8MB which is from 0xC00000000-0xC0800000 ... but then I have to be aware not to overwrite the kernel, so I will technically have less than 8MB . Is there a way so that the heap just continues

问题 Finished implementing the minimal Heap structure with awesome help from Micheal . Right now I have one thing missing so it dynamically grows. As you can see in this image, it isn't dynamic: Instead of having a fixed size when I do pmm_map_physical_virtual(0x800000,0xC0800000) , the max I can go to is 8MB which is from 0xC00000000-0xC0800000 ... but then I have to be aware not to overwrite the kernel, so I will technically have less than 8MB . Is there a way so that the heap just continues

问题 Finished implementing the minimal Heap structure with awesome help from Micheal . Right now I have one thing missing so it dynamically grows. As you can see in this image, it isn't dynamic: Instead of having a fixed size when I do pmm_map_physical_virtual(0x800000,0xC0800000) , the max I can go to is 8MB which is from 0xC00000000-0xC0800000 ... but then I have to be aware not to overwrite the kernel, so I will technically have less than 8MB . Is there a way so that the heap just continues

问题 Finished implementing the minimal Heap structure with awesome help from Micheal . Right now I have one thing missing so it dynamically grows. As you can see in this image, it isn't dynamic: Instead of having a fixed size when I do pmm_map_physical_virtual(0x800000,0xC0800000) , the max I can go to is 8MB which is from 0xC00000000-0xC0800000 ... but then I have to be aware not to overwrite the kernel, so I will technically have less than 8MB . Is there a way so that the heap just continues

问题 I am trying to learn the how to use Priority Queues, and there is one method I do not fully understand and would like some help as to how it works. That method is findMin. The part I want to understand is why the biggest number ends up in location 0 of the array? Then, since the list is sorted, its easy to find the smallest number in location [1] of the array. But why? Here is all the code I am looking at: public class BinaryHeap<AnyType extends Comparable<? super AnyType>> { /** * Construct