--- schema_version: "1" id: 8d33f35409a4ecde8d8c3ff8d1299e4dece88cd079c8199f097315cb17ad5a4f title: SessionPartition Class collection: legacydeveloper version: current locale: en-us portal_url: https://docs.salesforce.com/legacydeveloper/current/en-us/apexref/apex_class_cache_SessionPartition.md canonical_url: https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_SessionPartition.htm source_site: developer.salesforce.com content_type: documentation content_hash: 4141de6a1823df61bcf6ed653ca69ba4e5e36519f847f0542483fb88965b100a description: Contains methods to manage cache values in the session cache of a specific partition. --- # SessionPartition Class Contains methods to manage cache values in the session cache of a specific partition. ## Namespace [Cache](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_namespace_cache.htm "The Cache namespace contains methods for managing the platform cache.") ## Usage This class extends [Cache.Partition](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Partition.htm#apex_class_cache_Partition "Base class of Cache.OrgPartition and Cache.SessionPartition. Use the subclasses to manage the cache partition for org caches and session caches.") and inherits all of its non-static methods. Utility methods for creating and validating keys are not supported and can be called only from the Cache.Partition parent class. For a list of Cache.Partition methods, see [Partition Methods](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Partition.htm#apex_cache_Partition_methods). To get a session partition, call Cache.Session.getPartition and pass in a fully qualified partition name, as follows. Cache.SessionPartition sessionPartition = Cache.Session.getPartition('namespace.myPartition'); See [Cache Key Format for Partition Methods](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Partition.htm#key_format_section). ## Example This class is the controller for a sample Visualforce page (shown in the subsequent code sample). The controller shows how to use the methods of Cache.SessionPartition to manage a cache value on a particular partition. The controller takes inputs from the Visualforce page for the partition name, key name for a counter, and initial counter value. The controller contains default values for these inputs. When you click **Rerender** on the Visualforce page, the go() method is invoked and increases the counter by one. When you click **Remove Key**, the counter key is removed from the cache. The counter value gets reset to its initial value when it’s re-added to the cache. public with sharing class SessionPartitionController { // Name of a partition in the local namespace String partitionInput = 'local.myPartition'; // Name of the key String counterKeyInput = 'counter'; // Key initial value Integer counterInitValue = 0; // Session partition object Cache.SessionPartition sessionPartition; // Constructor of the controller for the Visualforce page. public SessionPartitionController() { } // Adds counter value to the cache. // This method is called when the Visualforce page loads. public void init() { // Create the partition instance based on the partition name sessionPartition = getPartition(); // Add counter to the cache with an initial value // or increment it if it's already there. if (!sessionPartition.contains(counterKeyInput)) { sessionPartition.put(counterKeyInput, counterInitValue); } else { sessionPartition.put(counterKeyInput, getCounter() + 1); } } // Returns the session partition based on the partition name // given in the Visualforce page or the default value. private Cache.SessionPartition getPartition() { if (sessionPartition == null) { sessionPartition = Cache.Session.getPartition(partitionInput); } return sessionPartition; } // Return counter from the cache. public Integer getCounter() { return (Integer)getPartition().get(counterKeyInput); } // Invoked by the Submit button to save input values // supplied by the user. public PageReference save() { // Reset the initial key value in the cache getPartition().put(counterKeyInput, counterInitValue); return null; } // Method invoked by the Rerender button on the Visualforce page. // Updates the values of various cached values. // Increases the values of counter and the MyData counter if those // cache values are still in the cache. public PageReference go() { // Get the partition object sessionPartition = getPartition(); // Increase the cached counter value or set it to 0 // if it's not cached. if (sessionPartition.contains(counterKeyInput)) { sessionPartition.put(counterKeyInput, getCounter() + 1); } else { sessionPartition.put(counterKeyInput, counterInitValue); } return null; } // Method invoked by the Remove button on the Visualforce page. // Removes the datetime cached value from the session cache. public PageReference remove() { getPartition().remove(counterKeyInput); return null; } // Get and set methods for accessing variables // that correspond to the input text fields on // the Visualforce page. public String getPartitionInput() { return partitionInput; } public String getCounterKeyInput() { return counterKeyInput; } public Integer getCounterInitValue() { return counterInitValue; } public void setPartitionInput(String partition) { this.partitionInput = partition; } public void setCounterKeyInput(String keyName) { this.counterKeyInput = keyName; } public void setCounterInitValue(Integer counterValue) { this.counterInitValue = counterValue; } } This is the Visualforce page that corresponds to the SessionPartitionController class.
Partition with Namespace Prefix:
Counter Key Name:
Counter Initial Value:
Cached Counter:
#### See Also - [_Apex Developer Guide_: Platform Cache](https://developer.salesforce.com/docs/atlas.en-us.264.0.apexcode.meta/apexcode/apex_cache_namespace_overview.htm "Apex Developer Guide: Platform Cache - HTML (New Window)")