DATAREDIS-369 - Avoid resource leak in RedisCache.

We now check the presence of a prefix which allows to identify the keys associated with the cache to either keep track of keys or use the prefix to remove them on clear.

This is a small fix intended to be back ported to the Evans (1.4.x) release train. Additional refactoring will be done for the Fowler release.

Original Pull Request: #122

src/test/java/org/springframework/data/redis/cache/RedisCacheUnitTests.java

@@ -0,0 +1,132 @@
+/*
+ * Copyright 2015 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.redis.cache;
+
+import static org.mockito.Matchers.*;
+import static org.mockito.Mockito.*;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.runners.MockitoJUnitRunner;
+import org.springframework.data.redis.connection.RedisConnection;
+import org.springframework.data.redis.connection.RedisConnectionFactory;
+import org.springframework.data.redis.connection.ReturnType;
+import org.springframework.data.redis.core.RedisTemplate;
+import org.springframework.data.redis.serializer.RedisSerializer;
+
+/**
+ * @author Christoph Strobl
+ */
+@SuppressWarnings("rawtypes")
+@RunWith(MockitoJUnitRunner.class)
+public class RedisCacheUnitTests {
+
+	private static final String CACHE_NAME = "foo";
+	private static final String PREFIX = "prefix:";
+	private static final byte[] PREFIX_BYTES = "prefix:".getBytes();
+	private static final byte[] KNOWN_KEYS_SET_NAME_BYTES = (CACHE_NAME + "~keys").getBytes();
+
+	private static final String KEY = "key";
+	private static final byte[] KEY_BYTES = KEY.getBytes();
+	private static final byte[] KEY_WITH_PREFIX_BYTES = (PREFIX + KEY).getBytes();
+
+	private static final String VALUE = "value";
+	private static final byte[] VALUE_BYTES = VALUE.getBytes();
+
+	private static final byte[] NO_PREFIX_BYTES = new byte[] {};
+	private static final long EXPIRATION = 1000;
+
+	RedisTemplate<?, ?> templateSpy;
+	@Mock RedisSerializer keySerializerMock;
+	@Mock RedisSerializer valueSerializerMock;
+	@Mock RedisConnectionFactory connectionFactoryMock;
+	@Mock RedisConnection connectionMock;
+
+	RedisCache cache;
+
+	@SuppressWarnings("unchecked")
+	@Before
+	public void setUp() {
+
+		RedisTemplate template = new RedisTemplate();
+		template.setConnectionFactory(connectionFactoryMock);
+		template.setKeySerializer(keySerializerMock);
+		template.setValueSerializer(valueSerializerMock);
+		template.afterPropertiesSet();
+
+		templateSpy = spy(template);
+
+		when(connectionFactoryMock.getConnection()).thenReturn(connectionMock);
+
+		when(keySerializerMock.serialize(any(byte[].class))).thenReturn(KEY_BYTES);
+		when(valueSerializerMock.serialize(any(byte[].class))).thenReturn(VALUE_BYTES);
+	}
+
+	/**
+	 * @see DATAREDIS-369
+	 */
+	@Test
+	public void putShouldNotKeepTrackOfKnownKeysWhenPrefixIsSet() {
+
+		cache = new RedisCache(CACHE_NAME, PREFIX_BYTES, templateSpy, EXPIRATION);
+		cache.put(KEY, VALUE);
+
+		verify(connectionMock, times(1)).set(eq(KEY_WITH_PREFIX_BYTES), eq(VALUE_BYTES));
+		verify(connectionMock, times(1)).expire(eq(KEY_WITH_PREFIX_BYTES), eq(EXPIRATION));
+		verify(connectionMock, never()).zAdd(eq(KNOWN_KEYS_SET_NAME_BYTES), eq(0D), any(byte[].class));
+	}
+
+	/**
+	 * @see DATAREDIS-369
+	 */
+	@Test
+	public void putShouldKeepTrackOfKnownKeysWhenNoPrefixIsSet() {
+
+		cache = new RedisCache(CACHE_NAME, NO_PREFIX_BYTES, templateSpy, EXPIRATION);
+		cache.put(KEY, VALUE);
+
+		verify(connectionMock, times(1)).set(eq(KEY_BYTES), eq(VALUE_BYTES));
+		verify(connectionMock, times(1)).expire(eq(KEY_BYTES), eq(EXPIRATION));
+		verify(connectionMock, times(1)).zAdd(eq(KNOWN_KEYS_SET_NAME_BYTES), eq(0D), eq(KEY_BYTES));
+	}
+
+	/**
+	 * @see DATAREDIS-369
+	 */
+	@Test
+	public void clearShouldRemoveKeysUsingKnownKeysWhenNoPrefixIsSet() {
+
+		cache = new RedisCache(CACHE_NAME, NO_PREFIX_BYTES, templateSpy, EXPIRATION);
+		cache.clear();
+
+		verify(connectionMock, times(1)).zRange(eq(KNOWN_KEYS_SET_NAME_BYTES), eq(0L), eq(127L));
+	}
+
+	/**
+	 * @see DATAREDIS-369
+	 */
+	@Test
+	public void clearShouldCallLuaScritpToRemoveKeysWhenPrefixIsSet() {
+
+		cache = new RedisCache(CACHE_NAME, PREFIX_BYTES, templateSpy, EXPIRATION);
+		cache.clear();
+
+		verify(connectionMock, times(1)).eval(any(byte[].class), eq(ReturnType.INTEGER), eq(0),
+				eq((PREFIX + "*").getBytes()));
+	}
+}