Module io.helidon.health.checks

Package io.helidon.health.checks

Class HeapMemoryHealthCheck

java.lang.Object

io.helidon.health.checks.HeapMemoryHealthCheck

All Implemented Interfaces:

HealthCheck

public class HeapMemoryHealthCheck
extends Object
implements HealthCheck

A health check that verifies whether the server is running out of Java heap space. If heap usage exceeds a specified threshold, then the health check will fail.

By default, this health check has a threshold of 98.0 (98.0%). If heap usage exceeds this level, then the server is considered to be unhealthy. This default can be modified using the "helidon.health.heapMemory.thresholdPercent" property. The threshold should be set as a percent, such as 50 for 50% or 99 for 99%.

This health check is automatically created and registered through CDI.

This health check can be referred to in properties as heapMemory. So for example, to exclude this health check from being exposed, use helidon.health.exclude: heapMemory.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	HeapMemoryHealthCheck.Builder	Fluent API builder for HeapMemoryHealthCheck.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	CONFIG_KEY_THRESHOLD_PERCENT	Config property key for heap memory threshold.
static final double	DEFAULT_THRESHOLD	Default threshold percentage.

Method Summary

Modifier and Type	Method	Description
static HeapMemoryHealthCheck.Builder	builder()	Create a new fluent API builder to configure a new health check.
HealthCheckResponse	call()	Call a health check.
static HeapMemoryHealthCheck	create()	Create a new heap memory health check with default configuration.
String	name()	Name of this health check, used in output when details are requested.
String	path()	Path of this health check, to support single health-check queries.
HealthCheckType	type()	Type of this health check.

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT_THRESHOLD

public static final double DEFAULT_THRESHOLD

Default threshold percentage.

See Also:

• Constant Field Values

CONFIG_KEY_THRESHOLD_PERCENT

public static final String CONFIG_KEY_THRESHOLD_PERCENT

Config property key for heap memory threshold.

See Also:

• Constant Field Values

Method Details

builder

public static HeapMemoryHealthCheck.Builder builder()

Create a new fluent API builder to configure a new health check.

Returns:

builder instance

create

public static HeapMemoryHealthCheck create()

Create a new heap memory health check with default configuration.

Returns:

a new health check

See Also:

• DEFAULT_THRESHOLD

type

public HealthCheckType type()

Description copied from interface: HealthCheck

Type of this health check.

Specified by:

type in interface HealthCheck

Returns:

type, defaults to HealthCheckType.LIVENESS

name

public String name()

Description copied from interface: HealthCheck

Name of this health check, used in output when details are requested.

Specified by:

name in interface HealthCheck

Returns:

name of this health check, defaults to simple class name

path

public String path()

Description copied from interface: HealthCheck

Path of this health check, to support single health-check queries.

Specified by:

path in interface HealthCheck

Returns:

path to use, by default returns HealthCheck.name()

call

public HealthCheckResponse call()

Description copied from interface: HealthCheck

Call a health check.

Specified by:

call in interface HealthCheck

Returns:

health response