jps
2.查看某java进程的信息
jinfo pid
3.java堆栈跟踪工具
jstack pid
4.查看gc情况，下面命令第四位标识打印间隔，第5位为打印多少次
jstat -gcutil pid 1000 5
5.查看java进程的内存映像工具
jmap -heap pid
6.查看当前java进程堆对象统计信息
jmap -histo pid
7.出问题再使用的命令，平时别用，dump出内存情况
jmap -dump:live,format=b,file=tmp.hprof pid
8.jdk自带的反解析工具
javap -verbose TestClass
java线程的状态有下面几种状态：/**
* Thread state for a thread which has not yet started.
*/
NEW,
/**
* Thread state for a runnable thread. A thread in the runnable
* state is executing in the Java virtual machine but it may
* be waiting for other resources from the operating system
* such as processor.
*/
RUNNABLE,
/**
* Thread state for a thread blocked waiting for a monitor lock.
* A thread in the blocked state is waiting for a monitor lock
* to enter a synchronized block/method or
* reenter a synchronized block/method after calling
* {@link Object#wait() Object.wait}.
*/
BLOCKED,
/**
* Thread state for a waiting thread.
* A thread is in the waiting state due to calling one of the
* following methods:
* <ul>
* <li>{@link Object#wait() Object.wait} with no timeout</li>
* <li>{@link #join() Thread.join} with no timeout</li>
* <li>{@link LockSupport#park() LockSupport.park}</li>
* </ul>
*
* <p>A thread in the waiting state is waiting for another thread to
* perform a particular action.
*
* For example, a thread that has called <tt>Object.wait()</tt>
* on an object is waiting for another thread to call
* <tt>Object.notify()</tt>or <tt>Object.notifyAll()</tt>on
* that object. A thread that has called <tt>Thread.join()</tt>
* is waiting for a specified thread to terminate.
*/
WAITING,
/**
* Thread state for a waiting thread with a specified waiting time.
* A thread is in the timed waiting state due to calling one of
* the following methods with a specified positive waiting time:
* <ul>
* <li>{@link #sleep Thread.sleep}</li>
* <li>{@link Object#wait(long) Object.wait} with timeout</li>
* <li>{@link #join(long) Thread.join} with timeout</li>
* <li>{@link LockSupport#parkNanos LockSupport.parkNanos}</li>
* <li>{@link LockSupport#parkUntil LockSupport.parkUntil}</li>
* </ul>
*/
TIMED_WAITING,
/**
* Thread state for a terminated thread.
* The thread has completed execution.
*/
TERMINATED
Windows通过任务管理器查看进程信息
在进程页签中查看Java进程，我是idea启动，因此可以在idea下查看相关进程
此外可以在详细信息页签下Ctrl+f搜索java
通过控制台查看进程信息
进入CMD，键入tasklist，可以查看所有的进程信息，包括进程ID、内存使用情况
查看Java相关的进程，可以添加过滤条件 tasklist | findstr "java" ，需要注意windows中字符串需要使用双引号，要不就不加也是可以的
如果是在IDEA中启动程序，可以借用idea的Terminal终端执行命令
taskkill 杀死进程
杀死进程使用taskkill /pid 指定进程id，如果无法杀死，可以尝试强制杀死taskkill /pid 进程id -t -f
可以看到idea控制台中进程已结束
通过tasklist | findstr 进程id 已经无法查询到该进程，说明进程终止成功
