Caffeine LoadCache

Since Camel 2.20

Only producer is supported

The Caffeine Loadcache component enables you to perform caching operations using the LoadingCache from Caffeine.

Maven users will need to add the following dependency to their pom.xml for this component:

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-caffeine</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

caffeine-loadcache://cacheName[?options]

You can append query options to the URI in the following format, ?option=value&option=#beanRef&…​

Configuring Options

Camel components are configured on two separate levels:

  • component level

  • endpoint level

Configuring Component Options

The component level is the highest level which holds general and common configurations that are inherited by the endpoints. For example a component may have security settings, credentials for authentication, urls for network connection and so forth.

Some components only have a few options, and others may have many. Because components typically have pre configured defaults that are commonly used, then you may often only need to configure a few options on a component; or none at all.

Configuring components can be done with the Component DSL, in a configuration file (application.properties|yaml), or directly with Java code.

Configuring Endpoint Options

Where you find yourself configuring the most is on endpoints, as endpoints often have many options, which allows you to configure what you need the endpoint to do. The options are also categorized into whether the endpoint is used as consumer (from) or as a producer (to), or used for both.

Configuring endpoints is most often done directly in the endpoint URI as path and query parameters. You can also use the Endpoint DSL as a type safe way of configuring endpoints.

A good practice when configuring options is to use Property Placeholders, which allows to not hardcode urls, port numbers, sensitive information, and other settings. In other words placeholders allows to externalize the configuration from your code, and gives more flexibility and reuse.

The following two sections lists all the options, firstly for the component followed by the endpoint.

Component Options

The Caffeine LoadCache component supports 17 options, which are listed below.

Name Description Default Type

action (producer)

To configure the default cache action. If an action is set in the message header, then the operation from the header takes precedence.

String

cacheLoader (producer)

To configure a CacheLoader in case of a LoadCache use.

CacheLoader

createCacheIfNotExist (producer)

Configure if a cache need to be created if it does exist or can’t be pre-configured.

boolean

evictionType (producer)

Set the eviction Type for this cache.

Enum values:

  • size_based

  • time_based

EvictionType

expireAfterAccessTime (producer)

Set the expire After Access Time in case of time based Eviction (in seconds).

int

expireAfterWriteTime (producer)

Set the expire After Access Write in case of time based Eviction (in seconds).

int

initialCapacity (producer)

Set the initial Capacity for the cache.

int

key (producer)

To configure the default action key. If a key is set in the message header, then the key from the header takes precedence.

Object

lazyStartProducer (producer)

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

boolean

maximumSize (producer)

Set the maximum size for the cache.

int

removalListener (producer)

Set a specific removal Listener for the cache.

RemovalListener

statsCounter (producer)

Set a specific Stats Counter for the cache stats.

StatsCounter

statsEnabled (producer)

To enable stats on the cache.

boolean

autowiredEnabled (advanced)

Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc.

boolean

configuration (advanced)

Sets the global component configuration.

CaffeineConfiguration

keyType (advanced)

The cache key type, default java.lang.Object.

String

valueType (advanced)

The cache value type, default java.lang.Object.

String

Endpoint Options

The Caffeine LoadCache endpoint is configured using URI syntax:

caffeine-loadcache:cacheName

with the following path and query parameters:

Path Parameters (1 parameters)

Name Description Default Type

cacheName (producer)

Required the cache name.

String

Query Parameters (15 parameters)

Name Description Default Type

action (producer)

To configure the default cache action. If an action is set in the message header, then the operation from the header takes precedence.

String

cacheLoader (producer)

To configure a CacheLoader in case of a LoadCache use.

CacheLoader

createCacheIfNotExist (producer)

Configure if a cache need to be created if it does exist or can’t be pre-configured.

boolean

evictionType (producer)

Set the eviction Type for this cache.

Enum values:

  • size_based

  • time_based

EvictionType

expireAfterAccessTime (producer)

Set the expire After Access Time in case of time based Eviction (in seconds).

int

expireAfterWriteTime (producer)

Set the expire After Access Write in case of time based Eviction (in seconds).

int

initialCapacity (producer)

Set the initial Capacity for the cache.

int

key (producer)

To configure the default action key. If a key is set in the message header, then the key from the header takes precedence.

Object

lazyStartProducer (producer)

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

boolean

maximumSize (producer)

Set the maximum size for the cache.

int

removalListener (producer)

Set a specific removal Listener for the cache.

RemovalListener

statsCounter (producer)

Set a specific Stats Counter for the cache stats.

StatsCounter

statsEnabled (producer)

To enable stats on the cache.

boolean

keyType (advanced)

The cache key type, default java.lang.Object.

String

valueType (advanced)

The cache value type, default java.lang.Object.

String

Spring Boot Auto-Configuration

When using caffeine-loadcache with Spring Boot make sure to use the following Maven dependency to have support for auto configuration:

<dependency>
  <groupId>org.apache.camel.springboot</groupId>
  <artifactId>camel-caffeine-starter</artifactId>
  <version>x.x.x</version>
  <!-- use the same version as your Camel core version -->
</dependency>

The component supports 36 options, which are listed below.

Name Description Default Type

camel.component.caffeine-cache.action

To configure the default cache action. If an action is set in the message header, then the operation from the header takes precedence.

String

camel.component.caffeine-cache.autowired-enabled

Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc.

true

Boolean

camel.component.caffeine-cache.cache-loader

To configure a CacheLoader in case of a LoadCache use. The option is a com.github.benmanes.caffeine.cache.CacheLoader type.

CacheLoader

camel.component.caffeine-cache.configuration

Sets the global component configuration. The option is a org.apache.camel.component.caffeine.CaffeineConfiguration type.

CaffeineConfiguration

camel.component.caffeine-cache.create-cache-if-not-exist

Configure if a cache need to be created if it does exist or can’t be pre-configured.

true

Boolean

camel.component.caffeine-cache.enabled

Whether to enable auto configuration of the caffeine-cache component. This is enabled by default.

Boolean

camel.component.caffeine-cache.eviction-type

Set the eviction Type for this cache.

EvictionType

camel.component.caffeine-cache.expire-after-access-time

Set the expire After Access Time in case of time based Eviction (in seconds).

300

Integer

camel.component.caffeine-cache.expire-after-write-time

Set the expire After Access Write in case of time based Eviction (in seconds).

300

Integer

camel.component.caffeine-cache.initial-capacity

Set the initial Capacity for the cache.

10000

Integer

camel.component.caffeine-cache.key

To configure the default action key. If a key is set in the message header, then the key from the header takes precedence. The option is a java.lang.Object type.

Object

camel.component.caffeine-cache.key-type

The cache key type, default java.lang.Object.

String

camel.component.caffeine-cache.lazy-start-producer

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

Boolean

camel.component.caffeine-cache.maximum-size

Set the maximum size for the cache.

10000

Integer

camel.component.caffeine-cache.removal-listener

Set a specific removal Listener for the cache. The option is a com.github.benmanes.caffeine.cache.RemovalListener type.

RemovalListener

camel.component.caffeine-cache.stats-counter

Set a specific Stats Counter for the cache stats. The option is a com.github.benmanes.caffeine.cache.stats.StatsCounter type.

StatsCounter

camel.component.caffeine-cache.stats-enabled

To enable stats on the cache.

false

Boolean

camel.component.caffeine-cache.value-type

The cache value type, default java.lang.Object.

String

camel.component.caffeine-loadcache.action

To configure the default cache action. If an action is set in the message header, then the operation from the header takes precedence.

String

camel.component.caffeine-loadcache.autowired-enabled

Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc.

true

Boolean

camel.component.caffeine-loadcache.cache-loader

To configure a CacheLoader in case of a LoadCache use. The option is a com.github.benmanes.caffeine.cache.CacheLoader type.

CacheLoader

camel.component.caffeine-loadcache.configuration

Sets the global component configuration. The option is a org.apache.camel.component.caffeine.CaffeineConfiguration type.

CaffeineConfiguration

camel.component.caffeine-loadcache.create-cache-if-not-exist

Configure if a cache need to be created if it does exist or can’t be pre-configured.

true

Boolean

camel.component.caffeine-loadcache.enabled

Whether to enable auto configuration of the caffeine-loadcache component. This is enabled by default.

Boolean

camel.component.caffeine-loadcache.eviction-type

Set the eviction Type for this cache.

EvictionType

camel.component.caffeine-loadcache.expire-after-access-time

Set the expire After Access Time in case of time based Eviction (in seconds).

300

Integer

camel.component.caffeine-loadcache.expire-after-write-time

Set the expire After Access Write in case of time based Eviction (in seconds).

300

Integer

camel.component.caffeine-loadcache.initial-capacity

Set the initial Capacity for the cache.

10000

Integer

camel.component.caffeine-loadcache.key

To configure the default action key. If a key is set in the message header, then the key from the header takes precedence. The option is a java.lang.Object type.

Object

camel.component.caffeine-loadcache.key-type

The cache key type, default java.lang.Object.

String

camel.component.caffeine-loadcache.lazy-start-producer

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

Boolean

camel.component.caffeine-loadcache.maximum-size

Set the maximum size for the cache.

10000

Integer

camel.component.caffeine-loadcache.removal-listener

Set a specific removal Listener for the cache. The option is a com.github.benmanes.caffeine.cache.RemovalListener type.

RemovalListener

camel.component.caffeine-loadcache.stats-counter

Set a specific Stats Counter for the cache stats. The option is a com.github.benmanes.caffeine.cache.stats.StatsCounter type.

StatsCounter

camel.component.caffeine-loadcache.stats-enabled

To enable stats on the cache.

false

Boolean

camel.component.caffeine-loadcache.value-type

The cache value type, default java.lang.Object.

String