--- schema_version: "1" id: b7991269e51e9a6023e128e1d1eeeabbe1a6527825cc5a69ab9223358eb6dbfc title: Session Class collection: legacydeveloper version: current locale: en-us portal_url: https://docs.salesforce.com/legacydeveloper/current/en-us/apexref/apex_class_cache_Session.md canonical_url: https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm source_site: developer.salesforce.com content_type: documentation content_hash: d6923265d3a76e312367c89dc0904703c2f86253c75a1de4a29f49720fe9a542 description: Use the Cache.Session class to add, retrieve, and manage values in the session cache. The session cache is active as long as the user’s Salesforce session is valid (the user is logged in, and the session is not expired).The Session class provides a constant that you can use when setting the time-to-live (TTL) value.Returns true if the session cache contains a cached value corresponding to the specified key.Returns true if the cache contains values for a specified set of keys.Returns the cached value corresponding to the specified key from the session cache.Returns the cached values corresponding to the specified set of keys from the session cache.Returns the cached value corresponding to the specified key from the session cache. Use this method if your cached value is a class that implements the CacheBuilder interface.Returns the average item size of all the keys fetched from the session cache, in bytes.Returns the average time taken to get a key from the session cache, in nanoseconds.Deprecated and available only in API versions 49.0 and earlier. Returns the average item size for keys in the session cache, in bytes.Returns the percentage of session cache capacity that has been used.Returns all keys that are stored in the session cache and visible to the invoking namespace.Returns the maximum item size of all the keys fetched from the session cache, in bytes.Returns the maximum time taken to get a key from the session cache, in nanoseconds.Deprecated and available only in API versions 49.0 and earlier. Returns the maximum item size for keys in the session cache, in bytes.Returns the miss rate in the session cache.Returns the name of the default cache partition.Returns the total number of keys in the session cache.Returns a partition from the session cache that corresponds to the specified partition name.Returns true if the session cache is available for use. The session cache isn’t available when an active session isn’t present, such as in asynchronous Apex or code called by asynchronous Apex. For example, if batch Apex causes an Apex trigger to execute, the session cache isn’t available in the trigger because the trigger runs in asynchronous context.Stores the specified key/value pair as a cached entry in the session cache. The put method can write only to the cache in your org’s namespace.Stores the specified key/value pair as a cached entry in the session cache and sets the cached value’s visibility.Stores the specified key/value pair as a cached entry in the session cache and sets the cached value’s lifetime.Stores the specified key/value pair as a cached entry in the session cache. This method also sets the cached value’s lifetime, visibility, and whether it can be overwritten by another namespace.Deletes the cached value corresponding to the specified key from the session cache.Deletes the cached value corresponding to the specified key from the session cache. Use this method if your cached value is a class that implements the CacheBuilder interface. --- # Session Class Use the Cache.Session class to add, retrieve, and manage values in the session cache. The session cache is active as long as the user’s Salesforce session is valid (the user is logged in, and the session is not expired). ## 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 **Cache Key Format** This table lists the format of the key parameter that some methods in this class take, such as put, get, and contains. | Key Format | Description | | --- | --- | | namespace.partition.key | Fully qualified key name. | | key | Refers to a partition marked as default when the namespace.partition prefix is omitted. | | local.partition.key | Use the local prefix to refer to the org’s namespace when the org doesn’t have a namespace defined. If the org has a namespace defined, the local prefix also refers to that org’s namespace. | ![Note](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/images/icon_note.png) #### Note - If no default partition is specified in the org, calling a cache method without fully qualifying the key name causes a ​Cache.Session.SessionCacheException to be thrown. - The local prefix in an installed managed package refers to the namespace of the subscriber org and not the package’s namespace. The cache put calls are not allowed in a partition that the invoking class doesn’t own. ## Example This class is the controller for a sample Visualforce page (shown in the subsequent code sample). The cached values are initially added to the cache by the init() method, which the Visualforce page invokes when it loads through the action attribute. The cache keys don’t contain the namespace.partition prefix. They all refer to a default partition in your org. The Visualforce page expects a partition named myPartition. To run this sample, create a default partition in your org with the name myPartition. The Visualforce page contains four output components. The first three components call get methods on the controller that return the following values from the cache: a date, data based on the MyData inner class, and a counter. The next output component uses the $Cache.Session global variable to get the cached string value for the key named output. Next, the $Cache.Session global variable is used again in the Visualforce page to iterate over the elements of a cached value of type List. The size of the list is also returned. The Visualforce page also contains two buttons. The Rerender button invokes the go() method on the controller. This method increases the values of the counter and the custom data in the cache. If you click **Rerender**, the two counters increase by one each time. The go() method retrieves the values of these counters from the cache, increments their values by one, and stores them again in the cache. The Remove button deletes the date-time value (with key datetime) from the cache. As a result, the value next to Cached datetime: is cleared on the page. public with sharing class SessionCacheController { // Inner class. // Used as the data type of a cache value. public with sharing class MyData { public String value { get; set; } public Integer counter { get; set; } public MyData(String value) { this.value = value; this.counter = 0; } public void inc() { counter++; } override public String toString() { return this.value + ':' + this.counter; } } // Apex List. // Used as the data type of a cached value. private List numbers = new List { 'ONE', 'TWO', 'THREE', 'FOUR', 'FIVE' }; // Constructor of the controller for the Visualforce page. public SessionCacheController() { } // Adds various values to the cache. // This method is called when the Visualforce page loads. public void init() { // All key values are not qualified by the namespace.partition // prefix because they use the default partition. // Add counter to the cache with initial value of 0 // or increment it if it's already there. if (!Cache.Session.contains('counter')) { Cache.Session.put('counter', 0); } else { Cache.Session.put('counter', getCounter() + 1); } // Add the datetime value to the cache only if it's not already there. if (!Cache.Session.contains('datetime')) { DateTime dt = DateTime.now(); Cache.Session.put('datetime', dt); } // Add the custom data to the cache only if it's not already there. if (!Cache.Session.contains('data')) { Cache.Session.put('data', new MyData('Some custom value')); } // Add a list of number to the cache if not already there. if (!Cache.Session.contains('list')) { Cache.Session.put('list', numbers); } // Add a string value to the cache if not already there. if (!Cache.Session.contains('output')) { Cache.Session.put('output', 'Cached text value'); } } // Return counter from the cache. public Integer getCounter() { return (Integer)Cache.Session.get('counter'); } // Return datetime value from the cache. public String getCachedDatetime() { DateTime dt = (DateTime)Cache.Session.get('datetime'); return dt != null ? dt.format() : null; } // Return cached value whose type is the inner class MyData. public String getCachedData() { MyData mydata = (MyData)Cache.Session.get('data'); return mydata != null ? mydata.toString() : 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() { // Increase the cached counter value or set it to 0 // if it's not cached. if (Cache.Session.contains('counter')) { Cache.Session.put('counter', getCounter() + 1); } else { Cache.Session.put('counter', 0); } // Get the custom data value from the cache. MyData d = (MyData)Cache.Session.get('data'); // Only if the data is already in the cache, update it. if (Cache.Session.contains('data')) { d.inc(); Cache.Session.put('data', d); } return null; } // Method invoked by the Remove button on the Visualforce page. // Removes the datetime cached value from the session cache. public PageReference remove() { Cache.Session.remove('datetime'); return null; } } This is the Visualforce page that corresponds to the SessionCacheController class.
Cached datetime:
Cached data:
Cached counter:
Output:
Repeat:  
List size:

This is the output of the page after clicking the Rerender button twice. The counter value could differ in your case if a key named counter was already in the cache before running this sample. Cached datetime:8/11/2015 1:58 PM Cached data:Some custom value:2 Cached counter:2 Output:Cached text value Repeat:ONE TWO THREE FOUR FIVE List size:5 - **[Session Constants](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_constants)** The Session class provides a constant that you can use when setting the time-to-live (TTL) value. - **[Session Methods](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_methods)** #### 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)") ## Session Constants The Session class provides a constant that you can use when setting the time-to-live (TTL) value. | Constant | Description | | --- | --- | | MAX\_TTL\_SECS | Represents the maximum amount of time, in seconds, to keep the cached value in the session cache. | ## Session Methods The following are methods for Session. All methods are static. - **[contains(key)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_contains)** Returns true if the session cache contains a cached value corresponding to the specified key. - **[contains(setOfKeys)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_contains_2)** Returns true if the cache contains values for a specified set of keys. - **[get(key)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_get)** Returns the cached value corresponding to the specified key from the session cache. - **[get(keys)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_get_3)** Returns the cached values corresponding to the specified set of keys from the session cache. - **[get(cacheBuilder, key)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_get_2)** Returns the cached value corresponding to the specified key from the session cache. Use this method if your cached value is a class that implements the CacheBuilder interface. - **[getAvgGetSize()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_getAvgGetSize)** Returns the average item size of all the keys fetched from the session cache, in bytes. - **[getAvgGetTime()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_getAvgGetTime)** Returns the average time taken to get a key from the session cache, in nanoseconds. - **[getAvgValueSize()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_getAvgValueSize)** **Deprecated and available only in API versions 49.0 and earlier.** Returns the average item size for keys in the session cache, in bytes. - **[getCapacity()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_getCapacity)** Returns the percentage of session cache capacity that has been used. - **[getKeys()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_getKeys)** Returns all keys that are stored in the session cache and visible to the invoking namespace. - **[getMaxGetSize()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_getMaxGetSize)** Returns the maximum item size of all the keys fetched from the session cache, in bytes. - **[getMaxGetTime()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_getMaxGetTime)** Returns the maximum time taken to get a key from the session cache, in nanoseconds. - **[getMaxValueSize()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_getMaxValueSize)** **Deprecated and available only in API versions 49.0 and earlier.** Returns the maximum item size for keys in the session cache, in bytes. - **[getMissRate()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_getMissRate)** Returns the miss rate in the session cache. - **[getName()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_getName)** Returns the name of the default cache partition. - **[getNumKeys()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_getNumKeys)** Returns the total number of keys in the session cache. - **[getPartition(partitionName)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_getPartition)** Returns a partition from the session cache that corresponds to the specified partition name. - **[isAvailable()](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_isAvailable)** Returns true if the session cache is available for use. The session cache isn’t available when an active session isn’t present, such as in asynchronous Apex or code called by asynchronous Apex. For example, if batch Apex causes an Apex trigger to execute, the session cache isn’t available in the trigger because the trigger runs in asynchronous context. - **[put(key, value)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_put_4)** Stores the specified key/value pair as a cached entry in the session cache. The put method can write only to the cache in your org’s namespace. - **[put(key, value, visibility)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_put_3)** Stores the specified key/value pair as a cached entry in the session cache and sets the cached value’s visibility. - **[put(key, value, ttlSecs)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_put_2)** Stores the specified key/value pair as a cached entry in the session cache and sets the cached value’s lifetime. - **[put(key, value, ttlSecs, visibility, immutable)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_put)** Stores the specified key/value pair as a cached entry in the session cache. This method also sets the cached value’s lifetime, visibility, and whether it can be overwritten by another namespace. - **[remove(key)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_remove)** Deletes the cached value corresponding to the specified key from the session cache. - **[remove(cacheBuilder, key)](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_Session.htm#apex_cache_Session_remove_2)** Deletes the cached value corresponding to the specified key from the session cache. Use this method if your cached value is a class that implements the CacheBuilder interface. ### contains(key) Returns true if the session cache contains a cached value corresponding to the specified key. #### Signature public static Boolean contains(String key) #### Parameters - **key**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") A case-sensitive string value that uniquely identifies a cached value. For information about the format of the key name, see [Usage](#usage_section). #### Return Value Type: [Boolean](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_boolean.htm#apex_methods_system_boolean "Contains methods for the Boolean primitive data type.") true if a cache entry is found. Othewise, false. ### contains(setOfKeys) Returns true if the cache contains values for a specified set of keys. #### Signature public static Map contains (Set keys) #### Parameters - **setOfKeys**: Type: Set <[String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.")\> A set of keys that uniquely identifies cached values. For information about the format of the key name, see [Usage](#usage_section). #### Return Value Type: Map <[String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type."), Boolean> Returns the cache key and corresponding Boolean value indicating that the key entry exists. The Boolean value is false if the key entry doesn't exist. #### Usage The number of input keys cannot exceed the maximum limit of 10. #### Example In this example, the code checks for the presence of multiple keys on the default partition. It fetches the cache key and the corresponding Boolean value for the key entry from the session cache of the default partition. Set keys = new Set{'key1','key2','key3','key4','key5'}; Map result = Cache.Session.contains(keys); for(String key : result.keySet()) { system.debug('key: ' + key); system.debug('Is Key Present in the cache : ' + result.get(key)); } In this example, the code checks for the presence of multiple keys on different partitions. It fetches the cache key and the corresponding Boolean value for the key entry from the session cache of different partitions. // Assuming there are three partitions p1, p2, p3 with default 'local' namespace Set keys = new Set{'local.p1.key','local.p2.key', 'local.p3.key'}; Map result = Cache.Session.contains(keys); for(String key : result.keySet()) { system.debug('key: ' + key); system.debug('Is Key Present in the cache : ' + result.get(key)); } ### get(key) Returns the cached value corresponding to the specified key from the session cache. #### Signature public static Object get(String key) #### Parameters - **key**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") A case-sensitive string value that uniquely identifies a cached value. For information about the format of the key name, see [Usage](#usage_section). #### Return Value Type: Object The cached value as a generic object type. Cast the returned value to the appropriate type. #### Usage Because Cache.Session.get() returns an object, we recommend that you cast the returned value to a specific type to facilitate use of the returned value. // Get a cached value Object obj = Cache.Session.get('ns1.partition1.orderDate'); // Cast return value to a specific data type DateTime dt2 = (DateTime)obj; If a Cache.Session.get() call doesn’t find the referenced key, it returns null. ### get(keys) Returns the cached values corresponding to the specified set of keys from the session cache. #### Signature public static Map get (Set keys) #### Parameters - **keys**: Type: Set <[String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.")\> A set of keys that uniquely identify cached values. For information about the format of the key name, see [Usage](#usage_section). #### Return Value Type: Map <[String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type."), Object> Returns the cache key and corresponding value. Returns null when no corresponding value is found for an input key. #### Usage The number of input keys cannot exceed the maximum limit of 10. #### Example Fetch multiple keys from the session cache of the default partition. Set keys = new Set{'key1','key2','key3','key4','key5'}; Map result = Cache.Session.get(keys); for(String key : result.keySet()) { system.debug('key: ' + key); system.debug('value: ' + result.get(key)); } Fetch multiple keys from the session cache of different partitions. // Assuming there are three partitions p1, p2, p3 with default 'local' namespace Set keys = new Set{'local.p1.key','local.p2.key', 'local.p3.key'}; Map result = Cache.Session.get(keys); for(String key : result.keySet()) { system.debug('key: ' + key); system.debug('value: ' + result.get(key)); } ### get(cacheBuilder, key) Returns the cached value corresponding to the specified key from the session cache. Use this method if your cached value is a class that implements the CacheBuilder interface. #### Signature public static Object get(System.Type cacheBuilder, String key) #### Parameters - **cacheBuilder**: Type: [System.Type](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_type.htm#apex_methods_system_type "Contains methods for getting the Apex type that corresponds to an Apex class and for instantiating new types.") The Apex class that implements the CacheBuilder interface. - **key**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") A case-sensitive string value that, combined with the class name corresponding to the cacheBuilder parameter, uniquely identifies a cached value. #### Return Value Type: Object The cached value as a generic object type. Cast the returned value to the appropriate type. #### Usage Because Cache.Session.get(cacheBuilder, key) returns an object, cast the returned value to a specific type to facilitate use of the returned value. return ((DateTime)Cache.Session.get(DateCache.class, 'datetime')).format(); ### getAvgGetSize() Returns the average item size of all the keys fetched from the session cache, in bytes. #### Signature public static Long getAvgGetSize() #### Return Value Type: [Long](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_long.htm#apex_methods_system_long "Contains methods for the Long primitive data type.") ### getAvgGetTime() Returns the average time taken to get a key from the session cache, in nanoseconds. #### Signature public static Long getAvgGetTime() #### Return Value Type: [Long](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_long.htm#apex_methods_system_long "Contains methods for the Long primitive data type.") ### getAvgValueSize() **Deprecated and available only in API versions 49.0 and earlier.** Returns the average item size for keys in the session cache, in bytes. #### Signature public static Long getAvgValueSize() #### Return Value Type: [Long](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_long.htm#apex_methods_system_long "Contains methods for the Long primitive data type.") ### getCapacity() Returns the percentage of session cache capacity that has been used. #### Signature public static Double getCapacity() #### Return Value Type: [Double](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_double.htm#apex_methods_system_double "Contains methods for the Double primitive data type.") Used cache as a percentage number. ### getKeys() Returns all keys that are stored in the session cache and visible to the invoking namespace. #### Signature public static Set getKeys() #### Return Value Type: Set<[String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.")\> A set containing all cache keys. ### getMaxGetSize() Returns the maximum item size of all the keys fetched from the session cache, in bytes. #### Signature public static Long getMaxGetSize() #### Return Value Type: [Long](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_long.htm#apex_methods_system_long "Contains methods for the Long primitive data type.") ### getMaxGetTime() Returns the maximum time taken to get a key from the session cache, in nanoseconds. #### Signature public static Long getMaxGetTime() #### Return Value Type: [Long](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_long.htm#apex_methods_system_long "Contains methods for the Long primitive data type.") ### getMaxValueSize() **Deprecated and available only in API versions 49.0 and earlier.** Returns the maximum item size for keys in the session cache, in bytes. #### Signature public static Long getMaxValueSize() #### Return Value Type: [Long](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_long.htm#apex_methods_system_long "Contains methods for the Long primitive data type.") ### getMissRate() Returns the miss rate in the session cache. #### Signature public static Double getMissRate() #### Return Value Type: [Double](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_double.htm#apex_methods_system_double "Contains methods for the Double primitive data type.") ### getName() Returns the name of the default cache partition. #### Signature public String getName() #### Return Value Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") The name of the default cache partition. ### getNumKeys() Returns the total number of keys in the session cache. #### Signature public static Long getNumKeys() #### Return Value Type: [Long](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_long.htm#apex_methods_system_long "Contains methods for the Long primitive data type.") ### getPartition(partitionName) Returns a partition from the session cache that corresponds to the specified partition name. #### Signature public static cache.SessionPartition getPartition(String partitionName) #### Parameters - **partitionName**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") A partition name that is qualified by the namespace, for example, namespace.partition. #### Return Value Type: [Cache.SessionPartition](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_class_cache_SessionPartition.htm#apex_class_cache_SessionPartition "Contains methods to manage cache values in the session cache of a specific partition.") #### Example After you get the session partition, you can add and retrieve the partition’s cache values. // Get partition Cache.SessionPartition sessionPart = Cache.Session.getPartition('myNs.myPartition'); // Retrieve cache value from the partition if (sessionPart.contains('BookTitle')) { String cachedTitle = (String)sessionPart.get('BookTitle'); } // Add cache value to the partition sessionPart.put('OrderDate', Date.today()); // Or use dot notation to call partition methods String cachedAuthor = (String)Cache.Session.getPartition('myNs.myPartition').get('BookAuthor'); ### isAvailable() Returns true if the session cache is available for use. The session cache isn’t available when an active session isn’t present, such as in asynchronous Apex or code called by asynchronous Apex. For example, if batch Apex causes an Apex trigger to execute, the session cache isn’t available in the trigger because the trigger runs in asynchronous context. #### Signature public static Boolean isAvailable() #### Return Value Type: [Boolean](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_boolean.htm#apex_methods_system_boolean "Contains methods for the Boolean primitive data type.") true if the session cache is available. Otherwise, false. ### put(key, value) Stores the specified key/value pair as a cached entry in the session cache. The put method can write only to the cache in your org’s namespace. #### Signature public static void put(String key, Object value) #### Parameters - **key**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") A string that uniquely identifies the value to be cached. For information about the format of the key name, see [Usage](#usage_section). - **value**: Type: Object The value to store in the cache. The cached value must be serializable. #### Return Value Type: void ### put(key, value, visibility) Stores the specified key/value pair as a cached entry in the session cache and sets the cached value’s visibility. #### Signature public static void put(String key, Object value, Cache.Visibility visibility) #### Parameters - **key**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") A string that uniquely identifies the value to be cached. For information about the format of the key name, see [Usage](#usage_section). - **value**: Type: Object The value to store in the cache. The cached value must be serializable. - **visibility**: Type: [Cache.Visibility](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_enum_cache_Visibility.htm "Use the Cache.Visibility enumeration in the Cache.Session or Cache.Org methods to indicate whether a cached value is visible only in the value’s namespace or in all namespaces.") Indicates whether the cached value is available only to Apex code that is executing in the same namespace or to Apex code executing from any namespace. #### Return Value Type: void ### put(key, value, ttlSecs) Stores the specified key/value pair as a cached entry in the session cache and sets the cached value’s lifetime. #### Signature public static void put(String key, Object value, Integer ttlSecs) #### Parameters - **key**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") A string that uniquely identifies the value to be cached. For information about the format of the key name, see [Usage](#usage_section). - **value**: Type: Object The value to store in the cache. The cached value must be serializable. - **ttlSecs**: Type: [Integer](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_integer.htm#apex_methods_system_integer "Contains methods for the Integer primitive data type.") The amount of time, in seconds, to keep the cached value in the session cache. The cached values remain in the cache as long as the Salesforce session hasn’t expired. The maximum value is 28,800 seconds or eight hours. The minimum value is 300 seconds or five minutes. #### Return Value Type: void ### put(key, value, ttlSecs, visibility, immutable) Stores the specified key/value pair as a cached entry in the session cache. This method also sets the cached value’s lifetime, visibility, and whether it can be overwritten by another namespace. #### Signature public static void put(String key, Object value, Integer ttlSecs, cache.Visibility visibility, Boolean immutable) #### Parameters - **key**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") A string that uniquely identifies the value to be cached. For information about the format of the key name, see [Usage](#usage_section). - **value**: Type: Object The value to store in the cache. The cached value must be serializable. - **ttlSecs**: Type: [Integer](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_integer.htm#apex_methods_system_integer "Contains methods for the Integer primitive data type.") The amount of time, in seconds, to keep the cached value in the session cache. The cached values remain in the cache as long as the Salesforce session hasn’t expired. The maximum value is 28,800 seconds or eight hours. The minimum value is 300 seconds or five minutes. - **visibility**: Type: [Cache.Visibility](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_enum_cache_Visibility.htm "Use the Cache.Visibility enumeration in the Cache.Session or Cache.Org methods to indicate whether a cached value is visible only in the value’s namespace or in all namespaces.") Indicates whether the cached value is available only to Apex code that is executing in the same namespace or to Apex code executing from any namespace. - **immutable**: Type: [Boolean](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_boolean.htm#apex_methods_system_boolean "Contains methods for the Boolean primitive data type.") Indicates whether the cached value can be overwritten by another namespace (false) or not (true). #### Return Value Type: void ### remove(key) Deletes the cached value corresponding to the specified key from the session cache. #### Signature public static Boolean remove(String key) #### Parameters - **key**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") A case-sensitive string value that uniquely identifies a cached value. For information about the format of the key name, see [Usage](#usage_section). #### Return Value Type: [Boolean](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_boolean.htm#apex_methods_system_boolean "Contains methods for the Boolean primitive data type.") true if the cache value was successfully removed. Otherwise, false. ### remove(cacheBuilder, key) Deletes the cached value corresponding to the specified key from the session cache. Use this method if your cached value is a class that implements the CacheBuilder interface. #### Signature public static Boolean remove(System.Type cacheBuilder, String key) #### Parameters - **cacheBuilder**: Type: [System.Type](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_type.htm#apex_methods_system_type "Contains methods for getting the Apex type that corresponds to an Apex class and for instantiating new types.") The Apex class that implements the CacheBuilder interface. - **key**: Type: [String](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_string.htm#apex_methods_system_string "Contains methods for the String primitive data type.") A case-sensitive string value that, combined with the class name corresponding to the cacheBuilder parameter, uniquely identifies a cached value. #### Return Value Type: [Boolean](https://developer.salesforce.com/docs/atlas.en-us.apexref.meta/apexref/apex_methods_system_boolean.htm#apex_methods_system_boolean "Contains methods for the Boolean primitive data type.") true if the cache value was successfully removed. Otherwise, false.