jvm 内存调整
top查看java占用的内存比较多
- top - :: up days, :, user, load average: 0.03, 0.05, 0.05
- Tasks: total, running, sleeping, stopped, zombie
- %Cpu(s): 0.0 us, 1.3 sy, 0.0 ni, 98.7 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
- KiB Mem : total, free, used, buff/cache
- KiB Swap: total, free, used. avail Mem
- PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
- root .598g S 0.0 20.5 :01.18 jsvc
- root .323g S 0.0 17.0 :32.59 jsvc
- root .136g S 0.0 14.6 :06.62 jsvc
- root S 0.0 9.2 :19.24 jsvc
可见每个占用了大概20%，还是比较高的，因为要部署新的服务，腾内存了
使用jstack查看一下进程的状态，其实也没什么用，不过我昨天刚学的java GC，就试用一下
- jstack -F
- Attaching to process ID , please wait...
- Debugger attached successfully.
- Server compiler detected.
- JVM version is 25.111-b14
- Deadlock Detection:
- No deadlocks found.
- Thread : (state = BLOCKED)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Interpreted frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Interpreted frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Interpreted frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
- Thread : (state = BLOCKED)
- - sun.misc.Unsafe.park(boolean, long) @bci= (Compiled frame; information may be imprecise)
- - java.util.concurrent.locks.LockSupport.park(java.lang.Object) @bci=, line= (Compiled frame)
- - java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await() @bci=, line= (Interpreted frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.getTask() @bci=, line= (Compiled frame)
- - java.util.concurrent.ThreadPoolExecutor.runWorker(java.util.concurrent.ThreadPoolExecutor$Worker) @bci=, line= (Interpreted frame)
- - java.util.concurrent.ThreadPoolExecutor$Worker.run() @bci=, line= (Interpreted frame)
- - java.lang.Thread.run() @bci=, line= (Interpreted frame)
后边不贴了，总之就是有大量的BLOCKED，这个程序说是bug导致的，下一个版本会修正，另外其他的进程实在IN_NATIVE状态，因为JAVA底层其实是C语言实现的，这个就是在执行C语言的调用，native
我竟然还以为是inactive，Naive
使用jstat分析一下gc，命令格式jstat -gc -t <PID>
- jstat -gc -t
- Timestamp S0C S1C S0U S1U EC EU OC OU MC MU CCSC CCSU YGC YGCT FGC FGCT GCT
- 484036.7 2048.0 2048.0 0.0 1296.0 694784.0 234952.5 1398272.0 259033.6 59136.0 57496.9 6400.0 6017.4 10.073 0.254 10.327
这里面S0C和S1C是两个survivor的容量，S0U和S1U是两个survivor已经使用的容量，EC和EU分别是新生代容量和已用容量，OC和OU是老年代的容量和已用，MC和MU是方法区的容量和使用大小，CCSC和CCSU是压缩类空间容量和使用大小，YGC是minor GC的次数，YGCT是minorGC的总计时间，FGC是major GC的次数，FGCT是major GC的时间，GCT是总共GC的占用时间。
其实这里还可以获取一下内存快照的，方法是
jmap -dump:format=b,file=heap.bin <pid>
file：保存路径及文件名
pid：进程编号（windows通过任务管理器查看，linux通过ps aux查看）
分析工具从http://www.eclipse.org/mat/下载，可惜我这里没有，所以说就算了吧
言归正传，用jmap分析下总的heap，heap就是堆，这里说下，堆和栈是有区别的，堆是存储变量，栈存储的是命令。堆是可以由应用程序来修改和申请空间，栈是由系统来管理的
- root@localhost:~# jmap -heap
- Attaching to process ID , please wait...
- Debugger attached successfully.
- Server compiler detected.
- JVM version is 25.111-b14
- using thread-local object allocation.
- Parallel GC with thread(s)
- Heap Configuration:
- MinHeapFreeRatio =
- MaxHeapFreeRatio =
- MaxHeapSize = (.0MB)
- NewSize = (.5MB)
- MaxNewSize = (.5MB)
- OldSize = (.5MB)
- NewRatio =
- SurvivorRatio =
- MetaspaceSize = (.796875MB)
- CompressedClassSpaceSize = (.0MB)
- MaxMetaspaceSize = MB
- G1HeapRegionSize = (.0MB)
- Heap Usage:
- PS Young Generation
- Eden Space:
- capacity = (.5MB)
- used = (.6439056396484MB)
- free = (.856094360351562MB)
- 96.33661100068511% used
- From Space:
- capacity = (.0MB)
- used = (.001068115234375MB)
- free = (.998931884765625MB)
- 50.05340576171875% used
- To Space:
- capacity = (.0MB)
- used = (.0MB)
- free = (.0MB)
- 0.0% used
- PS Old Generation
- capacity = (.5MB)
- used = (.53402709960938MB)
- free = (.9659729003906MB)
- 18.493887008393216% used
震惊！运维工程师用jmap分析jvm，竟然……
Eden看起来有点高了，但是其实这么说也是不公平的，Eden（伊甸园）区满了就会触发minorGC，把不活跃的对象清理掉，几次GC后还没有被清理掉的进入survivor，还能幸存的进入老年代，所以如果一个进程说Linux的哪一块内存没有去过，其实潜台词就是他老了(逃
不过Eden还是不能太小了，否则如果被活跃的对象占满了，GC不会处理这些对象，新的对象一直等着进不来，就会造成进程假死了，参考文献
http://www.cnblogs.com/jackchen001/p/6902909.html
或者温和一点，大量的对象放进老生代，导致频繁的full GC，full GC是要暂停程序的，并且会占用大量的CPU，导致性能下降
http://blog.csdn.net/hengyunabc/article/details/24924843
现在就比较简单了，使用java -XX就可以调整了
这里可以看到NewRatio是2，那么就是NewGeneration:OldGeneration = 1:2，new占了1/3的空间，old占了2/3,这里调整一下，把总体从原来的2G调整到1G就可以了，这样老年代空间和新生代空间都缩小了一半，YGC会频繁一点，但是YGC很快，不太会影响，只要老年区不被沾满就行，如果还不放心可以把新生代调大一点，SUN官方推荐新生代为整体的3/8。SurvivoRatio是连个Survivor区与Eden区的大小比值，8就是Eden:Survivor=8:2
- java -Xmx1024m -Xmn374m
这样调整后感觉好多了
参考文献
http://www.cnblogs.com/redcreen/archive/2011/05/04/2037057.html
http://www.importnew.com/1993.html
jvm 内存调整的更多相关文章
- JVM内存调整
JVM内存调整 先试着调整一下idea的 找到软件安装位置/bin/idea64.exe.vmoptions 给他直接整个起飞的,改成 -Xms512m -Xmx1500m 找到Java安装的位置/j ...
- 一次JVM内存调整
单台服务器8G内存,2核 系统里装了redis, rocketmq, mysql, zookeeper, 还有20个左右的微服务,每个微服务的jvm 参数 -Xms128m -Xmx256m -Xmn ...
- JBoss - 调整JVM内存 -Xms512m -Xmx1024m
$JBOSS-HOME/server/下有3个目录,all/default/minimal,它们是表示3种配置,全部的配置.默认配置.最小配置,我们在启动JBOSS服务时,可以指定 run –c al ...
- javaweb学习总结九(xml解析以及调整JVM内存大小)
一:解析XML文件的两种方式 1:dom,document object model,文档对象模型. 2:sax,simple API for XML. 3:比较dom和sax解析XML文件的优缺点 ...
- Java SE之调整JVM内存笔记
[文档整理系列] Java SE之调整JVM内存笔记 一般JVM内存限制是64Mbyte Eclipse下 Run as configrationArguments选项:-Xmx80m [设置虚拟机 ...
- JVM内存限制和调整
今天用java -jar执行一个jar文件提示内存不够,需要设置虚拟机的堆大小.以下是参考资料: 堆(Heap)和非堆(Non-heap)内存 按照官方的说法:“Java 虚拟机具有一个堆,堆是运行 ...
- 调整JVM内存大小
首次运行公司项目,出现了内存溢出,具体出现java.lang.OutOfMemoryError: PermGen space和java.lang.OutOfMemoryError:GC overhea ...
- Java调整JVM内存大小——（八）
JVM内存大小是有限的,有的时候程序过大时候会导致超出最大内存,产生下面异常: Exception in thread "main" java.lang.OutOfMemoryEr ...
- JVM内存管理------垃圾搜集器参数精解
本文是GC相关的最后一篇,这次LZ只是罗列一下hotspot JVM中垃圾搜集器相关的重点参数,以及各个参数的解释.废话不多说,这就开始. 垃圾搜集器文章传送门 JVM内存管理------JAVA语言 ...
随机推荐
- html to pdf小工具，支持evernote导出的html和firefox插件scrapbook
周末花了一天时间用wpf写了一个html转换为pdf的小工具. 已经在win7 32位 和win8 64两台机器上测试,目前基本可用,特拿来分享. 程序下载地址:http://pan.baidu.co ...
- 【BZOJ4285】使者 cdq分治+扫描线+树状数组
[BZOJ4285]使者 Description 公元 8192 年,人类进入星际大航海时代.在不懈的努力之下,人类占领了宇宙中的 n 个行星,并在这些行星之间修建了 n - 1 条星际航道,使得任意 ...
- interface Impl
public interface ActionBarOperations { void initSthOne(); void initSthTwo(); } public class ActionBa ...
- 动态设置progressBar的进度
progressDrawable = this.getResources().getDrawable(R.drawable.image); progressDrawable.setBounds(mSe ...
- DES加密解密 Java中运用
DES全称Data Encryption Standard,是一种使用密匙加密的块算法.现在认为是一种不安全的加密算法,因为现在已经有用穷举法攻破DES密码的报道了.尽管如此,该加密算法还是运用非常普 ...
- 微信小程序 --- 登录页面
思路:在个人中心页面,首先判断全局的 app.js 里面的 globalData 里面的 is_login 状态,并且判断 缓存数据中的 is_login 状态,如果都为真,就正常显示,如果有一个为假 ...
- BFS+状态压缩DP+二分枚举+TSP
http://acm.hdu.edu.cn/showproblem.php?pid=3681 Prison Break Time Limit: 5000/2000 MS (Java/Others) ...
- POM(project Object Model) Maven包管理依赖 pom.xml文件
什么是POM POM全称为“Project Object Model”,意思是工程对象模型.Maven工程使用pom.xml来指定工程配置信息,和其他文本信息.该配置文件以xml为格式,使用xml语法 ...
- CommonHelper 公共类
public static class CommonHelper 公共帮助类 using System.Collections.Generic; using System.Linq; using ...
- 删除Excel中的复选框等控件