Merge pull request #58 from salesforce/replace-guava-with-caffeine-fix

Configurable cache with Caffeine or Guava

src/main/java/com/force/i18n/grammar/parser/GrammaticalLabelSetLoader.java

@@ -155,10 +155,48 @@ public GrammaticalLabelSetLoader(LabelSetLoaderConfig config, boolean useSharedK
             this.seedKeyMap = null;
         }
 
-        this.cache = CaffeinatedGuava.build(getCacheBuilder(config), getCacheLoader());
+        this.cache = initCache(config);
     }
 
+    /**
+     * initialize internal cache that holds {@link GrammaticalLabelSet}.
+     *
+     * @param config a configuration to initialize this loader
+     * @return a {@code LoadingCache} object to use as a cache
+     */
+    protected LoadingCache<GrammaticalLabelSetDescriptor, GrammaticalLabelSet> initCache(LabelSetLoaderConfig config) {
+        // switch between Caffeine / Guava based on the config
+        return config.useCaffeine()
+                ? CaffeinatedGuava.build(getCaffeineCacheBuilder(config), getCacheLoader())
+                : getGuavaCacheBuilder(config).build(getCacheLoader());
+    }
+
+    /**
+     * @param config
+     *            a configuration to initialize this loader. if the configuration is set to use Guava, the
+     *            {@link UnsupportedOperationException} will be thrown.
+     * @return Caffeine instance to build a cache
+     * @deprecated This method is no longer used. In order to obtain a cache builder to modify cache settings, use
+     *             {@link #getCaffeineCacheBuilder(LabelSetLoaderConfig)} for Caffeine, or
+     *             {@link #getGuavaCacheBuilder(LabelSetLoaderConfig)} for Guava.
+     * @see #initCache(LabelSetLoaderConfig)
+     * @see LabelSetLoaderConfig#setCaffeine(boolean)
+     */
+    @Deprecated(since = "1.2.27", forRemoval = true)
     protected Caffeine<Object, Object> getCacheBuilder(LabelSetLoaderConfig config) {
+        if (!config.useCaffeine()) throw new UnsupportedOperationException();
+        return getCaffeineCacheBuilder(config);
+    }
+
+    /**
+     * Return a Caffeine-based cache builder instance.
+     * Override this method to replace, or edit cache option.
+     *
+     * @param config a config to initialize this loader
+     * @return Caffeine-based builder
+     * @see #initCache(LabelSetLoaderConfig)
+     */
+    protected Caffeine<Object, Object> getCaffeineCacheBuilder(LabelSetLoaderConfig config) {
         Caffeine<Object, Object> builder = Caffeine.newBuilder().initialCapacity(64);
 
         Duration expiration = config.getCacheExpireAfter();
@@ -173,6 +211,30 @@ protected Caffeine<Object, Object> getCacheBuilder(LabelSetLoaderConfig config)
         return builder;
     }
 
+    /**
+     * Return a Guava-based cache builder instance.
+     * Override this method to replace, or edit cache option.
+     *
+     * @param config a config to initialize this loader
+     * @return Guava-based builder
+     * @see #initCache(LabelSetLoaderConfig)
+     */
+    protected CacheBuilder<Object, Object> getGuavaCacheBuilder(LabelSetLoaderConfig config) {
+        CacheBuilder<Object, Object> builder = CacheBuilder.newBuilder().initialCapacity(64);
+
+        Duration expiration = config.getCacheExpireAfter();
+        if (!expiration.isZero() && !expiration.isNegative()) builder.expireAfterAccess(expiration);
+
+        long maxSize = config.getCacheMaxSize();
+        if (maxSize > 0) builder.maximumSize(maxSize);
+
+        if (config.isCacheStatsEnabled()) {
+            builder.recordStats();
+        }
+        return builder;
+    }
+
+
     protected CacheLoader<GrammaticalLabelSetDescriptor, GrammaticalLabelSet> getCacheLoader() {
         return new CacheLoader<GrammaticalLabelSetDescriptor, GrammaticalLabelSet>() {
             @Override

src/main/java/com/force/i18n/grammar/parser/LabelSetLoaderConfig.java

@@ -23,6 +23,7 @@ public class LabelSetLoaderConfig {
     public static final String RECORD_STATS = "loader.cache.stats";
     public static final String LOADER_EXPIRE_AFTER = "loader.cache.expireAfter";
     public static final String LOADER_MAX_SIZE = "loader.cache.maxSize";
+    public static final String USE_CAFFEINE = "loader.cache.useCaffeine";
 
     private final GrammaticalLabelSetDescriptor desc;
     private final GrammaticalLabelSetProvider parent;
@@ -33,6 +34,7 @@ public class LabelSetLoaderConfig {
     private boolean isCacheStatsEnabled;
     private Duration cacheExpireAfter; // expiration in minues
     private long cacheMaxSize; // max allowed entires
+    private boolean useCaffeine;
 
     public LabelSetLoaderConfig(GrammaticalLabelSetDescriptor baseDesc, GrammaticalLabelSetProvider parent) {
         this.desc = baseDesc;
@@ -45,6 +47,7 @@ public LabelSetLoaderConfig(GrammaticalLabelSetDescriptor baseDesc, GrammaticalL
         setCacheStatsEnabled(BasePropertyFile.stringToBoolean(getProperty(RECORD_STATS)));
         setCacheExpireAfter(Duration.ofMinutes(getPropertyLong(LOADER_EXPIRE_AFTER)));
         setCacheMaxSize(getPropertyLong(LOADER_MAX_SIZE));
+        setCaffeine(BasePropertyFile.stringToBoolean(getProperty(USE_CAFFEINE)));
     }
 
     public LabelSetLoaderConfig(LabelSetLoaderConfig copyFrom) {
@@ -56,6 +59,7 @@ public LabelSetLoaderConfig(LabelSetLoaderConfig copyFrom) {
         setCacheStatsEnabled(copyFrom.isCacheStatsEnabled());
         setCacheExpireAfter(copyFrom.getCacheExpireAfter());
         setCacheMaxSize(copyFrom.getCacheMaxSize());
+        setCaffeine(copyFrom.useCaffeine());
     }
 
     public static String getProperty(String prop) {
@@ -136,13 +140,23 @@ public LabelSetLoaderConfig setCacheMaxSize(long newVal) {
         return this;
     }
 
+    public LabelSetLoaderConfig setCaffeine(boolean useCaffeine) {
+        this.useCaffeine = useCaffeine;
+        return this;
+    }
+
+    public boolean useCaffeine() {
+        return this.useCaffeine;
+    }
+
     @Override
     public String toString() {
         StringBuilder sb = new StringBuilder();
         sb.append("stats=").append(this.isCacheStatsEnabled)
                 .append(", expire=").append(this.cacheExpireAfter)
                 .append(", size=").append(this.cacheMaxSize)
-                .append(", dir=").append(this.cacheDir.toAbsolutePath());
+                .append(", dir=").append(this.cacheDir.toAbsolutePath())
+                .append(", useCaffeine=").append(this.useCaffeine);
         return sb.toString();
     }
 }

src/main/java/com/force/i18n/grammaticus.properties

@@ -52,3 +52,6 @@ loader.cache.expireAfter=0
 
 # maximum size of cache entry. This cache key is LabelSetDescriptor(language). no limit for 0.
 loader.cache.maxSize=0
+
+# use Caffeine as internal cache otherwise, Guava LoadingCache will be used.
+loader.cache.useCaffeine=true

src/test/java/com/force/i18n/grammar/parser/GrammaticalLabelTest.java

@@ -7,6 +7,8 @@
 
 package com.force.i18n.grammar.parser;
 
+import static org.junit.Assert.assertThrows;
+
 import java.io.IOException;
 import java.lang.reflect.Field;
 import java.net.URL;
@@ -547,11 +549,24 @@ public void testCacheConfig() throws InterruptedException {
 
         GrammaticalLabelSetDescriptor desc = getDescriptor();
 
-        // Test expiration
         LabelSetLoaderConfig config = new LabelSetLoaderConfig(desc, null);
+        GrammaticalLabelSetLoader loader = new GrammaticalLabelSetLoader(config);
+        // default is Ceffeine.  comparing with the class name because the class is not public
+        assertEquals("CaffeinatedGuavaLoadingCache", loader.getCache().getClass().getSimpleName());
+
+        // try switching to Guava cache.
+        config.setCaffeine(false);
+        GrammaticalLabelSetLoader guavaLoader = new GrammaticalLabelSetLoader(config);
+        assertEquals("LocalLoadingCache", guavaLoader.getCache().getClass().getSimpleName());
+
+        assertThrows(UnsupportedOperationException.class, () -> guavaLoader.getCacheBuilder(config));
+
+        // Test expiration
+        // re-construct the loader with Caffeine and set expiration period to 1ms
+        config.setCaffeine(true);
         config.setCacheExpireAfter(Duration.ofMillis(1));
+        loader = new GrammaticalLabelSetLoader(config);
 
-        GrammaticalLabelSetLoader loader = new GrammaticalLabelSetLoader(config);
         loader.getSet(ENGLISH);
         Thread.sleep(1);
         assertNull(loader.getCache().getIfPresent(desc));
@@ -580,12 +595,12 @@ public void testCacheConfig() throws InterruptedException {
 
         // Caffeine does not evict prior the threadshold, but after the size crossed
         loader.getSet(FRENCH);
-        Thread.sleep(1);
+        Thread.sleep(5);
         assertEquals(3, loader.getCache().size());
         assertNotNull(loader.getCache().getIfPresent(desc.getForOtherLanguage(FRENCH)));
 
         loader.getSet(GERMAN);
-        Thread.sleep(1);
+        Thread.sleep(5);
         assertEquals(3, loader.getCache().size());
         assertNotNull(loader.getCache().getIfPresent(desc.getForOtherLanguage(GERMAN)));
     }