JSON Thread Dump Format

The JSON text is an object with a member named "threadDump" that is an object with the following members:
threadDump members
Name Data type Optional Description
formatVersion number no The format version. Its value is 2.
processId number no The process identifier (pid) of the VM that generated the thread dump.
time string no The timestamp, in ISO 8601 format, when the thread dump was generated.
runtimeVersion string no The {@linkplain java.lang.Runtime.Version runtime version} of the VM that generated the thread dump.
threadContainers array no The array of thread "groupings". The first element is the root grouping/container with name "<root>".

Each element in the "threadContainers" array is an object that represents a grouping/container of threads with the following members:

threadContainers members
Name Data type Optional Description
container string no The thread container name. The name is unique.
parent string or null no The thread container parent's name or {@code null} for the root container.
owner number or null no The {@linkplain java.lang.Thread#threadId() thread identifier} of the thread that owns the thread container or {@code null} if no owner.
threads array no The array of threads in the thread grouping/container.
threadCount number yes The number of threads in the thread grouping/container. If the thread dump includes all virtual threads then this count is the same as the number of elements in the threads array. If all virtual threads are not included then it may be larger than the number of elements in the threads array.

Each element in a "threads" array is an object with the following members:

threads members
Name Data type Optional Description
tid number no The {@linkplain java.lang.Thread#threadId() thread identifier}.
time string no The timestamp, in ISO 8601 format, when the thread was sampled.
name string no The {@linkplain java.lang.Thread#getName() thread name}.
state string no The string representation of the {@linkplain java.lang.Thread#getState() thread state}.
virtual boolean yes {@code true} if the thread is a {@linkplain java.lang.Thread#isVirtual() virtual thread}.
carrier number yes The thread identifier of the carrier thread when this thread is a mounted virtual thread.
stack array no The thread stack. The elements in the array are of type string with the string representation of a {@linkplain java.lang.StackTraceElement stack trace element}. If the thread stack has one or more elements, then the first element is the top of the stack.
parkBlocker object yes The object responsible for the thread parking. Its members identify the blocker object, and the exclusive owner thread if owned.
blockedOn string yes The {@linkplain java.util.Objects#toIdentityString(Object) identity string} of the object that the thread is blocked on waiting to enter/re-enter a synchronization method or block.
waitingOn string yes The {@linkplain java.util.Objects#toIdentityString(Object) identity string} of the object that the thread is {@linkplain java.lang.Object#wait() waiting} to be notified.
monitorsOwned array yes The objects for which a monitor is owned by the thread.

A "parkBlocker" object has the following members:

parkBlocker members
Name Data type Optional Description
object string no The {@linkplain java.util.Objects#toIdentityString(Object) identity string} of the {@linkplain java.util.concurrent.locks.LockSupport#park(Object) blocker object} responsible for the thread parking.
owner number yes The thread identifier of the exclusive owner thread when the parkBlocker is an {@link java.util.concurrent.locks.AbstractOwnableSynchronizer}.

Each element in a "monitorsOwned" array is an object with the following members:

monitorsOwned members
Name Data type Optional Description
depth number no The stack depth at which the monitors are owned.
locks array no The elements of the array are of type string or null. An element of type string has a value that is the {@linkplain java.util.Objects#toIdentityString(Object) identity string} of the object for which the monitor is owned by the thread. The element is of type null when the object has been eliminated.