9.2. Use the Default Cache

Procedure 9.2. Add and Remove Data from the Cache

1. Add an entry, replacing key and value with the desired key and value:

   cache.put("key", "value");

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2. Confirm that the entry is present in the cache:

   assertEquals(1, cache.size());
   assertTrue(cache.containsKey("key"));

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3. Remove the entry from the cache:

   Object v = cache.remove("key");

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4. Confirm that the entry is no longer present in the cache:

   assertEquals("value", v);
   assertTrue(cache.isEmpty());

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Procedure 9.3. Adding and Replacing a Key Value

• Add an entry key with value as the key's value.

  cache.put("key", "value");

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Procedure 9.4. Replacing a Key Value

1. The following code searches for keys (named key and key2). If the two specific keys beings searched for are not found, JBoss Data Grid creates two new keys with the specified key names and values.

   cache.putIfAbsent("key", "newValue");
   cache.putIfAbsent("key2", "value2");

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2. The following code confirms that the value of the stored key equals the value we wanted to store.

   assertEquals(cache.get("key"), "value");
   assertEquals(cache.get("key2"), "value2");

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Procedure 9.5. Adjust the Data Life

1. Alter the key's lifespan value:

   cache.put("key", "value", 5, TimeUnit.SECONDS);

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2. Check if the cache contains the key:

   assertTrue(cache.containsKey("key"));

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3. After the allocated lifespan time has expired, the key is no longer in the cache:

   Thread.sleep(10000);
   assertFalse(cache.containsKey("key"));

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