Infinispan 8. 2 User Guide. Infinispan supports indexing and searching of Java objects stored in the grid using powerful search APIs which complement its main Map- like API. Historically, searching was first available in Infinispan via Apache Lucene's API but since version 6. Infinispan provides its own query API based on a simple and expressive internal DSL. Searching with the new API is available for both embedded and remote clients while the Lucene based API is only available to embedded clients. The remote querying capability is further described in the Hot Rod client chapter. The infinispan- query module. This module adds indexing and querying capabilities to Infinispan. It uses Hibernate Search and Apache Lucene to index and search objects in the cache. It allows users to obtain objects within the cache without needing to know the keys to each object that they want to obtain. You can search your objects based on some of its properties. For example to retrieve all red cars (exact metadata match), or all books about a specific topic (full text search and relevance scoring). The queries can be expressed as Lucene queries, built directly using the Lucene Query API or built with the help of Hibernate Search Query DSL. Alternatively, you can also use Infinispan’s own query DSL which most users might find easier to use than the one based on Lucene at the cost of not being able to access some of the powerful capabilities which are specific to the underlying Lucene implementation. Configuration. Indexing must be enabled in the configuration (as explained in XML Configuration or Programmatic configuration ). This will trigger automatic indexing of objects stored in the cache; there are several different ways to specify how these objects need to be indexed explained in the following paragraphs. To run queries you use the Search. Manager which exposes all necessary methods to get started. Simple example. We’re going to store Book instances in Infinispan; each Book will be defined as in the following example; we have to choose which properties are indexed, and for each property we can optionally choose advanced indexing options using the annotations defined in the Hibernate Search project. Indexedpublicclass. Book . Notable differences with Hibernate Search. By default, if you are looking for a caching solution for your Java based enterprise application, the tendency is to go with Java Caches.Are you new to Oracle Community? Are you an experienced member who wants to help out our new users? Check out our new Getting Started group, and join today! Welcome to the official Infinispan user guide. This comprehensive document will guide you through every last detail of Infinispan, however can be a poor starting. An intent is an abstract description of an operation to be performed. It can be used with startActivity to launch an Activity, broadcastIntent to send it to any. Java Cryptography Architecture Oracle Providers Documentation for Java Platform Standard Edition 7. ![]() Using @Document. Id to mark a field as identifier does not apply to Infinispan values; in Infinispan Query the identifier for all @Indexed objects is the key used to store the value. You can still customize how the key is indexed using a combination of @Transformable , @Provided. Id , custom types and custom Field. Bridge implementations. Requirements for the Key: @Transformable and @Provided. Id. The key for each value needs to be indexed as well, and the key instance must be transformed in a String. Infinispan includes some default transformation routines to encode common primitives, but to use a custom key you must provide an implementation of org. Transformer . Registering a Transformer via annotations. You can annotate your key type with org. Transformable : @Transformable(transformer = Custom. Transformer. class). Custom. Key . Configuration via XMLTo enable indexing via XML, you need to add the < indexing /> element to your cache configuration, and optionally pass additional properties to the embedded Hibernate Search engine: < infinispan> < cache- containerdefault- cache=. For the complete reference of properties to define, refer to the Hibernate Search documentation . Automatic configuration< local- cachename=. For replicated and local caches, the indexing is configured to be persisted on disk and not shared with any other processes. Also, it is configured so that minimum delay exists between the moment an object is indexed and the moment it is available for searches (near real time). The auto config adds the following properties for replicated and local caches: Property namevaluedescriptionhibernate. More details at Hibernate Search documentationhibernate. More details at Hibernate Search documentationhibernate. Lucene Directory. Infinispan Query isn’t aware of where you store the indexes, it just passes the configuration of which Lucene Directory implementation you want to use to the Hibernate Search engine. There are several Lucene Directory implementations bundled, and you can plug your own or add third party implementations: the Directory is the IO API for Lucene to store the indexes. The most common Lucene Directory implementations used with Infinispan Query are: Ram - stores the index in a local map to the node. This index can’t be shared. Filesystem - stores the index in a locally mounted filesystem. This could be a network shared FS, but sharing this way is generally not recommended. Infinispan - stores the index in a different dedicated Infinispan cache. This cache can be configured as replicated or distributed, to share the index among nodes. See also the dedicated chapter on the Lucene Directory in this guide. Of course having a shared index vs. Using programmatic configuration and index mapping. In the following example we start Infinispan programmatically, avoiding XML configuration files, and also map an object Author which is to be stored in the grid and made searchable on two properties but without annotating the class. Search. Mapping mapping = new Search. Mapping(). mapping. Author. class). indexed(). Id(). . property(. Cache modes and managing indexes. Index management is currently controlled by the Configuration. Index. Local. Only() setter, or the < indexing index=. If you set this to true, only modifications made locally on each node are considered in indexing. Otherwise, remote changes are considered too. Regarding actually configuring a Lucene directory, refer to the Hibernate Search documentation on how to pass in the appropriate Lucene configuration via the Properties object passed to Query. Helper. 1. 5. 4. 1. LOCALIn local mode, you may use any Lucene Directory implementation. Also the option index. Local. Only isn’t meaningful. REPLICATIONIn replication mode, each node can have its own local copy of the index. So indexes can either be stored locally on each node (RAMDirectory, FSDirectory, etc) but you need to set index. Local. Only to false , so that each node will apply needed updates it receives from other nodes in addition to the updates started locally. Any Directory implementation can be used, but you have to make sure that when a new node is started it receives an up to date copy of the index; typically rsync is well suited for this task, but being an external operation you might end up with a slightly out- of- sync index, especially if updates are very frequent. Alternately, if you use some form of shared storage for indexes (see Sharing the Index ), you then have to set index. Local. Only to true so that each node will apply only the changes originated locally; in this case there’s no risk in having an out- of- sync index, but to avoid write contention on the index you should make sure that a single node is . Again, the Hibernate Search reference documentation describes means to use a JMS queue or JGroups to send indexing tasks to a master node. The diagram below shows a replicated deployment, in which each node has a local index. DISTRIBUTIONFor these 2 cache modes, you need to use a shared index and set index. Local. Only to true. The diagram below shows a deployment with a shared index. Note that while not mandatory, a shared index can be used for replicated (vs. INVALIDATIONIndexing or searching of elements under INVALIDATION mode is not supported. Sharing the Index. The most simple way to share an index is to use some form of shared storage for the indexes, like an FSDirectory on a shared disk; however this form is problematic as the FSDirectory relies on specific locking semantics which are often incompletely implemented on network filesystems, or not reliable enough; if you go for this approach make sure to search for potential problems on the Lucene mailing lists for other experiences and workarounds. Good luck, test well. There are many alternative Directory implementations you can find, one of the most suited approaches when working with Infinispan is of course to store the index in an Infinispan cache: have a look at the Infinispan. Directory. Provider , as all Infinispan based layers it can be combined with persistent Cache. Loaders to keep the index on a shared filesystem without the locking issues, or alternatively in a database, cloud storage, or any other Cache. Loader implementation; you could backup the index in the same store used to backup your values. For full documentation on clustering the Lucene engine, refer to the Hibernate Search documentation to properly configure it clustered. Clustering the Index in Infinispan. Again the configuration details are in the Hibernate Search reference, in particular in the infinispan- directories section. This backend will by default start a secondary Infinispan Cache. Manager, and optionally take another Infinispan configuration file: don’t reuse the same configuration or you will start grids recursively! It is currently not possible to share the same Cache. Manager. 1. 5. 7. Rebuilding the Index. Occasionally you might need to rebuild the Lucene index by reconstructing it from the data stored in the Cache. You need to rebuild the index if you change the definition of what is indexed on your types, or if you change for example some Analyzer parameter, as Analyzers affect how the index is defined. Also, you might need to rebuild the index if you had it destroyed by some system administration mistake. To rebuild the index just get a reference to the Mass. Indexer and start it; beware if might take some time as it needs to reprocess all data in the grid! Search. Manager search. Manager = Search. Search. Manager(cache). Manager. get. Mass. Indexer(). start(); This is also available as a start JMX operation on the Mass. Indexer MBean registered under the name org. Query,manager=. Obtaining query statistics.
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