Modifier and Type	Class and Description
public static interface	ProcessHandle.Info Information snapshot about the process.

Method Summary

Modifier and Type	Method and Description
public static Stream<ProcessHandle>	Returns: a Stream of ProcessHandles for all processes allProcesses() Returns a snapshot of all processes visible to the current process.
public Stream<ProcessHandle>	Returns: a sequential Stream of ProcessHandles for processes that are direct children of the process children() Returns a snapshot of the current direct children of the process.
public int	Returns: a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object. compareTo(ProcessHandle the ProcessHandle to be compared other) Redeclares java.lang.Comparable.compareTo. Compares this ProcessHandle with the specified ProcessHandle for order.
public static ProcessHandle	Returns: a ProcessHandle for the current process current() Returns a ProcessHandle for the current process.
public Stream<ProcessHandle>	Returns: a sequential Stream of ProcessHandles for processes that are descendants of the process descendants() Returns a snapshot of the descendants of the process.
public boolean	Returns: `true` if termination was successfully requested, otherwise `false` destroy() Requests the process to be killed.
public boolean	Returns: `true` if termination was successfully requested, otherwise `false` destroyForcibly() Requests the process to be killed forcibly.
public boolean	Returns: `true` if the `other` object is non-null, is of the same implementation class and represents the same system process; otherwise returns `false` equals(Object another object other) Returns `true` if `other` object is non-null, is of the same implementation, and represents the same system process; otherwise it returns `false`.
public int	Returns: a hash code value for this object hashCode() Returns a hash code value for this ProcessHandle.
public ProcessHandle.Info	Returns: a snapshot of information about the process, always non-null info() Returns a snapshot of information about the process.
public boolean	Returns: `true` if the process represented by this `ProcessHandle` object has not yet terminated isAlive() Tests whether the process represented by this `ProcessHandle` is alive.
public static Optional<ProcessHandle>	Returns: an `Optional<ProcessHandle>` of the PID for the process; the `Optional` is empty if the process does not exist of(long a native process ID pid) Returns an `Optional<ProcessHandle>` for an existing native process.
public CompletableFuture<ProcessHandle>	Returns: a new `CompletableFuture<ProcessHandle>` for the ProcessHandle onExit() Returns a `CompletableFuture<ProcessHandle>` for the termination of the process.
public Optional<ProcessHandle>	Returns: an `Optional<ProcessHandle>` of the parent process; the `Optional` is empty if the child process does not have a parent or if the parent is not available, possibly due to operating system limitations parent() Returns an `Optional<ProcessHandle>` for the parent process.
public long	Returns: the native process ID of the process pid() Returns the native process ID of the process.
public boolean	Returns: `true` if the implementation of `destroy` normally terminates the process; otherwise, `destroy` forcibly terminates the process supportsNormalTermination() Returns `true` if the implementation of `destroy` normally terminates the process.

Method Detail

allProcesses	back to summary
public static Stream<ProcessHandle> allProcesses() Returns a snapshot of all processes visible to the current process. Note that processes are created and terminate asynchronously. There is no guarantee that a process in the stream is alive or that no other processes may have been created since the inception of the snapshot. Returns:Stream<ProcessHandle> a Stream of ProcessHandles for all processes Exceptions UnsupportedOperationException: if the implementation does not support this operation

allProcesses

back to summary

public static Stream<ProcessHandle> allProcesses()

Returns a snapshot of all processes visible to the current process.

Note that processes are created and terminate asynchronously. There is no guarantee that a process in the stream is alive or that no other processes may have been created since the inception of the snapshot.

Returns:Stream<ProcessHandle>

a Stream of ProcessHandles for all processes

Exceptions

UnsupportedOperationException:: if the implementation does not support this operation

children back to summary

children	back to summary
public Stream<ProcessHandle> children() Returns a snapshot of the current direct children of the process. The `parent` of a direct child process is the process. Typically, a process that is `not alive` has no children. Note that processes are created and terminate asynchronously. There is no guarantee that a process is `alive`. Returns:Stream<ProcessHandle> a sequential Stream of ProcessHandles for processes that are direct children of the process

public Stream<ProcessHandle> children()

Returns a snapshot of the current direct children of the process. The parent of a direct child process is the process. Typically, a process that is not alive has no children.

Note that processes are created and terminate asynchronously. There is no guarantee that a process is alive.

Returns:Stream<ProcessHandle>: a sequential Stream of ProcessHandles for processes that are direct children of the process

compareTo back to summary

compareTo	back to summary
public int compareTo(ProcessHandle other) Redeclares java.lang.Comparable.compareTo. Compares this ProcessHandle with the specified ProcessHandle for order. The order is not specified, but is consistent with `Object#equals`, which returns `true` if and only if two instances of ProcessHandle are of the same implementation and represent the same system process. Comparison is only supported among objects of same implementation. If attempt is made to mutually compare two different implementations of `ProcessHandle`s, `ClassCastException` is thrown. Parameters other:ProcessHandle the ProcessHandle to be compared Returns:int a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object. Annotations @Override Exceptions NullPointerException: if the specified object is null ClassCastException: if the specified object is not of same class as this object

public int compareTo(ProcessHandle other)

Redeclares java.lang.Comparable.compareTo.

Compares this ProcessHandle with the specified ProcessHandle for order. The order is not specified, but is consistent with Object#equals, which returns true if and only if two instances of ProcessHandle are of the same implementation and represent the same system process. Comparison is only supported among objects of same implementation. If attempt is made to mutually compare two different implementations of ProcessHandles, ClassCastException is thrown.

Parameters

other:ProcessHandle: the ProcessHandle to be compared

Returns:int

a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.

Annotations

@Override

Exceptions

NullPointerException:: if the specified object is null
ClassCastException:: if the specified object is not of same class as this object

current back to summary

current	back to summary
public static ProcessHandle current() Returns a ProcessHandle for the current process. The ProcessHandle cannot be used to destroy the current process, use `System.exit` instead. Returns:ProcessHandle a ProcessHandle for the current process Exceptions UnsupportedOperationException: if the implementation does not support this operation

public static ProcessHandle current()

Returns a ProcessHandle for the current process. The ProcessHandle cannot be used to destroy the current process, use System.exit instead.

Returns:ProcessHandle

a ProcessHandle for the current process

Exceptions

UnsupportedOperationException:: if the implementation does not support this operation

descendants back to summary

descendants	back to summary
public Stream<ProcessHandle> descendants() Returns a snapshot of the descendants of the process. The descendants of a process are the children of the process plus the descendants of those children, recursively. Typically, a process that is `not alive` has no children. Note that processes are created and terminate asynchronously. There is no guarantee that a process is `alive`. Returns:Stream<ProcessHandle> a sequential Stream of ProcessHandles for processes that are descendants of the process

public Stream<ProcessHandle> descendants()

Returns a snapshot of the descendants of the process. The descendants of a process are the children of the process plus the descendants of those children, recursively. Typically, a process that is not alive has no children.

Note that processes are created and terminate asynchronously. There is no guarantee that a process is alive.

Returns:Stream<ProcessHandle>: a sequential Stream of ProcessHandles for processes that are descendants of the process

destroy back to summary

destroy	back to summary
public boolean destroy() Requests the process to be killed. Whether the process represented by this `ProcessHandle` object is `normally terminated` or not is implementation dependent. Forcible process destruction is defined as the immediate termination of the process, whereas normal termination allows the process to shut down cleanly. If the process is not alive, no action is taken. The operating system access controls may prevent the process from being killed. The `java.util.concurrent.CompletableFuture` from `onExit` is `completed` when the process has terminated. Note The process may not terminate immediately. For example, `isAlive()` may return true for a brief period after `destroy()` is called. Returns:boolean `true` if termination was successfully requested, otherwise `false` Exceptions IllegalStateException: if the process is the current process

public boolean destroy()

Requests the process to be killed. Whether the process represented by this ProcessHandle object is normally terminated or not is implementation dependent. Forcible process destruction is defined as the immediate termination of the process, whereas normal termination allows the process to shut down cleanly. If the process is not alive, no action is taken. The operating system access controls may prevent the process from being killed.

The java.util.concurrent.CompletableFuture from onExit is completed when the process has terminated.

Note

The process may not terminate immediately. For example, isAlive() may return true for a brief period after destroy() is called.

Returns:boolean

true if termination was successfully requested, otherwise false

Exceptions

IllegalStateException:: if the process is the current process

destroyForcibly back to summary

destroyForcibly	back to summary
public boolean destroyForcibly() Requests the process to be killed forcibly. The process represented by this `ProcessHandle` object is forcibly terminated. Forcible process destruction is defined as the immediate termination of the process, whereas normal termination allows the process to shut down cleanly. If the process is not alive, no action is taken. The operating system access controls may prevent the process from being killed. The `java.util.concurrent.CompletableFuture` from `onExit` is `completed` when the process has terminated. Note The process may not terminate immediately. For example, `isAlive()` may return true for a brief period after `destroyForcibly()` is called. Returns:boolean `true` if termination was successfully requested, otherwise `false` Exceptions IllegalStateException: if the process is the current process

public boolean destroyForcibly()

Requests the process to be killed forcibly. The process represented by this ProcessHandle object is forcibly terminated. Forcible process destruction is defined as the immediate termination of the process, whereas normal termination allows the process to shut down cleanly. If the process is not alive, no action is taken. The operating system access controls may prevent the process from being killed.

The java.util.concurrent.CompletableFuture from onExit is completed when the process has terminated.

Note

The process may not terminate immediately. For example, isAlive() may return true for a brief period after destroyForcibly() is called.

Returns:boolean

true if termination was successfully requested, otherwise false

Exceptions

IllegalStateException:: if the process is the current process

equals back to summary

equals	back to summary
public boolean equals(Object other) Returns `true` if `other` object is non-null, is of the same implementation, and represents the same system process; otherwise it returns `false`. Implementation Note It is implementation specific whether ProcessHandles with the same PID represent the same system process. ProcessHandle implementations should contain additional information to uniquely identify the process. For example, the start time of the process could be used to determine if the PID has been re-used. The implementation of `equals` should return `true` for two ProcessHandles with the same PID unless there is information to distinguish them. Parameters other:Object another object Returns:boolean `true` if the `other` object is non-null, is of the same implementation class and represents the same system process; otherwise returns `false` Annotations @Override

public boolean equals(Object other)

Returns true if other object is non-null, is of the same implementation, and represents the same system process; otherwise it returns false.

Implementation Note

It is implementation specific whether ProcessHandles with the same PID represent the same system process. ProcessHandle implementations should contain additional information to uniquely identify the process. For example, the start time of the process could be used to determine if the PID has been re-used. The implementation of equals should return true for two ProcessHandles with the same PID unless there is information to distinguish them.

Parameters

other:Object: another object

Returns:boolean

true if the other object is non-null, is of the same implementation class and represents the same system process; otherwise returns false

Annotations

@Override

hashCode back to summary

hashCode	back to summary
public int hashCode() Returns a hash code value for this ProcessHandle. The hashcode value follows the general contract for `Object#hashCode()`. The value is a function of the `pid()` value and may be a function of additional information to uniquely identify the process. If two ProcessHandles are equal according to the `equals` method, then calling the hashCode method on each of the two objects must produce the same integer result. Returns:int a hash code value for this object Annotations @Override

public int hashCode()

Returns a hash code value for this ProcessHandle. The hashcode value follows the general contract for Object#hashCode(). The value is a function of the pid() value and may be a function of additional information to uniquely identify the process. If two ProcessHandles are equal according to the equals method, then calling the hashCode method on each of the two objects must produce the same integer result.

Returns:int

a hash code value for this object

Annotations

@Override

info back to summary

info	back to summary
public ProcessHandle.Info info() Returns a snapshot of information about the process. A `ProcessHandle.Info` instance has accessor methods that return information about the process if it is available. Returns:ProcessHandle.Info a snapshot of information about the process, always non-null

public ProcessHandle.Info info()

Returns a snapshot of information about the process.

A ProcessHandle.Info instance has accessor methods that return information about the process if it is available.

Returns:ProcessHandle.Info: a snapshot of information about the process, always non-null

isAlive back to summary

isAlive	back to summary
public boolean isAlive() Tests whether the process represented by this `ProcessHandle` is alive. Process termination is implementation and operating system specific. The process is considered alive as long as the PID is valid. Returns:boolean `true` if the process represented by this `ProcessHandle` object has not yet terminated

public boolean isAlive()

Tests whether the process represented by this ProcessHandle is alive. Process termination is implementation and operating system specific. The process is considered alive as long as the PID is valid.

Returns:boolean: true if the process represented by this ProcessHandle object has not yet terminated

of back to summary

of	back to summary
public static Optional<ProcessHandle> of(long pid) Returns an `Optional<ProcessHandle>` for an existing native process. Parameters pid:long a native process ID Returns:Optional<ProcessHandle> an `Optional<ProcessHandle>` of the PID for the process; the `Optional` is empty if the process does not exist Exceptions UnsupportedOperationException: if the implementation does not support this operation

public static Optional<ProcessHandle> of(long pid)

Returns an Optional<ProcessHandle> for an existing native process.

Parameters

pid:long: a native process ID

Returns:Optional<ProcessHandle>

an Optional<ProcessHandle> of the PID for the process; the Optional is empty if the process does not exist

Exceptions

UnsupportedOperationException:: if the implementation does not support this operation

onExit back to summary

onExit	back to summary
public CompletableFuture<ProcessHandle> onExit() Returns a `CompletableFuture<ProcessHandle>` for the termination of the process. The `java.util.concurrent.CompletableFuture` provides the ability to trigger dependent functions or actions that may be run synchronously or asynchronously upon process termination. When the process has terminated the CompletableFuture is `completed` regardless of the exit status of the process. The `onExit` method can be called multiple times to invoke independent actions when the process exits. Calling `onExit().get()` waits for the process to terminate and returns the ProcessHandle. The future can be used to check if the process is `done` or to `wait` for it to terminate. `Cancelling` the CompletableFuture does not affect the Process. API Note The process may be observed to have terminated with `isAlive` before the `CompletableFuture` is completed and dependent actions are invoked. Returns:CompletableFuture<ProcessHandle> a new `CompletableFuture<ProcessHandle>` for the ProcessHandle Exceptions IllegalStateException: if the process is the current process

public CompletableFuture<ProcessHandle> onExit()

Returns a CompletableFuture<ProcessHandle> for the termination of the process. The java.util.concurrent.CompletableFuture provides the ability to trigger dependent functions or actions that may be run synchronously or asynchronously upon process termination. When the process has terminated the CompletableFuture is completed regardless of the exit status of the process. The onExit method can be called multiple times to invoke independent actions when the process exits.

Calling onExit().get() waits for the process to terminate and returns the ProcessHandle. The future can be used to check if the process is done or to wait for it to terminate. Cancelling the CompletableFuture does not affect the Process.

API Note

The process may be observed to have terminated with isAlive before the CompletableFuture is completed and dependent actions are invoked.

Returns:CompletableFuture<ProcessHandle>

a new CompletableFuture<ProcessHandle> for the ProcessHandle

Exceptions

IllegalStateException:: if the process is the current process

parent back to summary

parent	back to summary
public Optional<ProcessHandle> parent() Returns an `Optional<ProcessHandle>` for the parent process. Note that Processes in a zombie state usually don't have a parent. Returns:Optional<ProcessHandle> an `Optional<ProcessHandle>` of the parent process; the `Optional` is empty if the child process does not have a parent or if the parent is not available, possibly due to operating system limitations

public Optional<ProcessHandle> parent()

Returns an Optional<ProcessHandle> for the parent process. Note that Processes in a zombie state usually don't have a parent.

Returns:Optional<ProcessHandle>: an Optional<ProcessHandle> of the parent process; the Optional is empty if the child process does not have a parent or if the parent is not available, possibly due to operating system limitations

pid back to summary

pid	back to summary
public long pid() Returns the native process ID of the process. The native process ID is an identification number that the operating system assigns to the process. The operating system may reuse the process ID after a process terminates. Use `equals` or `compareTo` to compare ProcessHandles. Returns:long the native process ID of the process Exceptions UnsupportedOperationException: if the implementation does not support this operation

public long pid()

Returns the native process ID of the process. The native process ID is an identification number that the operating system assigns to the process. The operating system may reuse the process ID after a process terminates. Use equals or compareTo to compare ProcessHandles.

Returns:long

the native process ID of the process

Exceptions

UnsupportedOperationException:: if the implementation does not support this operation

supportsNormalTermination back to summary

supportsNormalTermination	back to summary
public boolean supportsNormalTermination() Returns `true` if the implementation of `destroy` normally terminates the process. Returns `false` if the implementation of `destroy` forcibly and immediately terminates the process. Returns:boolean `true` if the implementation of `destroy` normally terminates the process; otherwise, `destroy` forcibly terminates the process

public boolean supportsNormalTermination()

Returns true if the implementation of destroy normally terminates the process. Returns false if the implementation of destroy forcibly and immediately terminates the process.

Returns:boolean: true if the implementation of destroy normally terminates the process; otherwise, destroy forcibly terminates the process

java.lang back to summary

public Interface ProcessHandle.Info

Known Direct Implementers: java.lang.ProcessHandleImpl.Info

Information snapshot about the process. The attributes of a process vary by operating system and are not available in all implementations. Information about processes is limited by the operating system privileges of the process making the request. The return types are Optional<T> allowing explicit tests and actions if the value is available.

Since: 9

Method Summary

Modifier and Type	Method and Description
public Optional<String[]>	Returns: an `Optional<String[]>` of the arguments of the process arguments() Returns an array of Strings of the arguments of the process.
public Optional<String>	Returns: an `Optional<String>` of the executable pathname of the process command() Returns the executable pathname of the process.
public Optional<String>	Returns: an `Optional<String>` of the command line of the process commandLine() Returns the command line of the process.
public Optional<Instant>	Returns: an `Optional<Instant>` of the start time of the process startInstant() Returns the start time of the process.
public Optional<Duration>	Returns: an `Optional<Duration>` for the accumulated total cputime totalCpuDuration() Returns the total cputime accumulated of the process.
public Optional<String>	Returns: an `Optional<String>` for the user of the process user() Return the user of the process.

Method Detail

arguments back to summary

arguments	back to summary
public Optional<String[]> arguments() Returns an array of Strings of the arguments of the process. API Note On some platforms, native applications are free to change the arguments array after startup and this method may only show the changed values. Returns:Optional<String[]> an `Optional<String[]>` of the arguments of the process

public Optional<String[]> arguments()

Returns an array of Strings of the arguments of the process.

API Note

On some platforms, native applications are free to change the arguments array after startup and this method may only show the changed values.

Returns:Optional<String[]>: an Optional<String[]> of the arguments of the process

command back to summary

command	back to summary
public Optional<String> command() Returns the executable pathname of the process. Returns:Optional<String> an `Optional<String>` of the executable pathname of the process

public Optional<String> command()

Returns the executable pathname of the process.

Returns:Optional<String>: an Optional<String> of the executable pathname of the process

commandLine back to summary

commandLine	back to summary
public Optional<String> commandLine() Returns the command line of the process. If `command()` and `arguments()` return non-empty optionals, this is simply a convenience method which concatenates the values of the two functions separated by spaces. Otherwise, it will return a best-effort, platform dependent representation of the command line. API Note Note that the returned executable pathname and the arguments may be truncated on some platforms due to system limitations. The executable pathname may contain only the name of the executable without the full path information. It is undecidable whether white space separates different arguments or is part of a single argument. Returns:Optional<String> an `Optional<String>` of the command line of the process

public Optional<String> commandLine()

Returns the command line of the process.

If command() and arguments() return non-empty optionals, this is simply a convenience method which concatenates the values of the two functions separated by spaces. Otherwise, it will return a best-effort, platform dependent representation of the command line.

API Note

Note that the returned executable pathname and the arguments may be truncated on some platforms due to system limitations.

The executable pathname may contain only the name of the executable without the full path information. It is undecidable whether white space separates different arguments or is part of a single argument.

Returns:Optional<String>: an Optional<String> of the command line of the process

startInstant back to summary

startInstant	back to summary
public Optional<Instant> startInstant() Returns the start time of the process. Returns:Optional<Instant> an `Optional<Instant>` of the start time of the process

public Optional<Instant> startInstant()

Returns the start time of the process.

Returns:Optional<Instant>: an Optional<Instant> of the start time of the process

totalCpuDuration back to summary

totalCpuDuration	back to summary
public Optional<Duration> totalCpuDuration() Returns the total cputime accumulated of the process. Returns:Optional<Duration> an `Optional<Duration>` for the accumulated total cputime

public Optional<Duration> totalCpuDuration()

Returns the total cputime accumulated of the process.

Returns:Optional<Duration>: an Optional<Duration> for the accumulated total cputime

user back to summary

user	back to summary
public Optional<String> user() Return the user of the process. Returns:Optional<String> an `Optional<String>` for the user of the process

public Optional<String> user()

Return the user of the process.

Returns:Optional<String>: an Optional<String> for the user of the process

public Interface ProcessHandle

Nested and Inner Type Summary

Method Summary

Method Detail

public Interface ProcessHandle.Info

Method Summary

Method Detail