Package org.graalvm.tools.insight.heap

Class HeapDump.Builder

java.lang.Object

org.graalvm.tools.insight.heap.HeapDump.Builder

All Implemented Interfaces:

Closeable, AutoCloseable

Enclosing class:

HeapDump

public final class HeapDump.Builder
extends Object
implements Closeable

Builder to construct content of the heap dump file.

Builder builder = HeapDump.newHeapBuilder(new FileOutputStream(hprof));
builder.dumpHeap((heap) -> {
    final ClassInstance classActor = heap.newClass("cartoons.Actor").
        field("name", String.class).
        field("friend", Object.class).
        field("age", int.class).
        dumpClass();
    final ObjectInstance jerry = heap.newInstance(classActor).
        put("name", heap.dumpString("Jerry")).
        putInt("age", 47).
        // field 'friend' remains null
        dumpInstance();
    final ObjectInstance tom = heap.newInstance(classActor).
        put("name", heap.dumpString("Tom")).
        put("friend", jerry).
        putInt("age", 32).
        dumpInstance();
    final ClassInstance classMain = heap.newClass("cartoons.Main").
        field("tom", classActor).
        field("jerry", classActor).
        field("thread", java.lang.Thread.class).
        dumpClass();

    HeapDump.InstanceBuilder mainBuilder = heap.newInstance(classMain);
    final ObjectInstance main = mainBuilder.id();
    mainBuilder.put("tom", tom).put("jerry", jerry);

    ObjectInstance cathingThread = heap.newThread("Catching Jerry").
        addStackFrame(classActor, "tom", "Actor.java", -1, jerry, tom, main).
        addStackFrame(classMain, "main", "Main.java", -1, main).
        dumpThread();

    mainBuilder.put("thread", cathingThread).dumpInstance();
});

Since:

21.1

Method Summary

Modifier and Type	Method	Description
void	close()
void	dumpHeap(long timeStamp, Consumer<HeapDump> generator)	Generates heap dump with an explicitly specified time stamp.
void	dumpHeap(Consumer<HeapDump> generator)	Generates heap dump.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

dumpHeap

public void dumpHeap(Consumer<HeapDump> generator)
              throws IOException

Generates heap dump.

Builder builder = HeapDump.newHeapBuilder(new FileOutputStream(hprof));
builder.dumpHeap((heap) -> {
    final ClassInstance classActor = heap.newClass("cartoons.Actor").
        field("name", String.class).
        field("friend", Object.class).
        field("age", int.class).
        dumpClass();
    final ObjectInstance jerry = heap.newInstance(classActor).
        put("name", heap.dumpString("Jerry")).
        putInt("age", 47).
        // field 'friend' remains null
        dumpInstance();
    final ObjectInstance tom = heap.newInstance(classActor).
        put("name", heap.dumpString("Tom")).
        put("friend", jerry).
        putInt("age", 32).
        dumpInstance();
    final ClassInstance classMain = heap.newClass("cartoons.Main").
        field("tom", classActor).
        field("jerry", classActor).
        field("thread", java.lang.Thread.class).
        dumpClass();

    HeapDump.InstanceBuilder mainBuilder = heap.newInstance(classMain);
    final ObjectInstance main = mainBuilder.id();
    mainBuilder.put("tom", tom).put("jerry", jerry);

    ObjectInstance cathingThread = heap.newThread("Catching Jerry").
        addStackFrame(classActor, "tom", "Actor.java", -1, jerry, tom, main).
        addStackFrame(classMain, "main", "Main.java", -1, main).
        dumpThread();

    mainBuilder.put("thread", cathingThread).dumpInstance();
});

Parameters:

generator - callback that performs the heap generating operations

Throws:

IOException - when an I/O error occurs

Since:

21.1

See Also:

• HeapDump.newHeapBuilder(java.io.OutputStream)

dumpHeap

public void dumpHeap(long timeStamp,
 Consumer<HeapDump> generator)
              throws IOException

Generates heap dump with an explicitly specified time stamp. Should there be multiple dumps in a single file, it is expected the subsequent values of timeStamp are not going to be decreasing.

Builder builder = HeapDump.newHeapBuilder(new FileOutputStream(hprof));
builder.dumpHeap((heap) -> {
    final ClassInstance classActor = heap.newClass("cartoons.Actor").
        field("name", String.class).
        field("friend", Object.class).
        field("age", int.class).
        dumpClass();
    final ObjectInstance jerry = heap.newInstance(classActor).
        put("name", heap.dumpString("Jerry")).
        putInt("age", 47).
        // field 'friend' remains null
        dumpInstance();
    final ObjectInstance tom = heap.newInstance(classActor).
        put("name", heap.dumpString("Tom")).
        put("friend", jerry).
        putInt("age", 32).
        dumpInstance();
    final ClassInstance classMain = heap.newClass("cartoons.Main").
        field("tom", classActor).
        field("jerry", classActor).
        field("thread", java.lang.Thread.class).
        dumpClass();

    HeapDump.InstanceBuilder mainBuilder = heap.newInstance(classMain);
    final ObjectInstance main = mainBuilder.id();
    mainBuilder.put("tom", tom).put("jerry", jerry);

    ObjectInstance cathingThread = heap.newThread("Catching Jerry").
        addStackFrame(classActor, "tom", "Actor.java", -1, jerry, tom, main).
        addStackFrame(classMain, "main", "Main.java", -1, main).
        dumpThread();

    mainBuilder.put("thread", cathingThread).dumpInstance();
});

Parameters:

timeStamp - time when the heap dump is supposed to be taken in milliseconds

generator - callback that performs the heap generating operations

Throws:

IOException - when an I/O error occurs

Since:

21.1

See Also:

• HeapDump.newHeapBuilder(java.io.OutputStream)

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException