Clean caches between tests

Author: garydgregory

src/main/java/org/apache/commons/lang3/time/AbstractFormatCache.java

@@ -89,7 +89,14 @@ public int hashCode() {
      */
     static final int NONE = -1;
 
-    private static final ConcurrentMap<ArrayKey, String> cDateTimeInstanceCache = new ConcurrentHashMap<>(7);
+    private static final ConcurrentMap<ArrayKey, String> dateTimeInstanceCache = new ConcurrentHashMap<>(7);
+
+    /**
+     * Clears the cache.
+     */
+    static void clear() {
+        dateTimeInstanceCache.clear();
+    }
 
     /**
      * Gets a date/time format for the specified styles and locale.
@@ -104,7 +111,7 @@ public int hashCode() {
     static String getPatternForStyle(final Integer dateStyle, final Integer timeStyle, final Locale locale) {
         final Locale safeLocale = LocaleUtils.toLocale(locale);
         final ArrayKey key = new ArrayKey(dateStyle, timeStyle, safeLocale);
-        return cDateTimeInstanceCache.computeIfAbsent(key, k -> {
+        return dateTimeInstanceCache.computeIfAbsent(key, k -> {
             try {
                 final DateFormat formatter;
                 if (dateStyle == null) {

src/main/java/org/apache/commons/lang3/time/FastDateParser.java

@@ -42,6 +42,7 @@
 import java.util.concurrent.ConcurrentMap;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
+import java.util.stream.Stream;
 
 import org.apache.commons.lang3.ArraySorter;
 import org.apache.commons.lang3.LocaleUtils;
@@ -630,7 +631,7 @@ public String toString() {
     // helper classes to parse the format string
 
     @SuppressWarnings("unchecked") // OK because we are creating an array with no entries
-    private static final ConcurrentMap<Locale, Strategy>[] caches = new ConcurrentMap[Calendar.FIELD_COUNT];
+    private static final ConcurrentMap<Locale, Strategy>[] CACHES = new ConcurrentMap[Calendar.FIELD_COUNT];
 
     private static final Strategy ABBREVIATED_YEAR_STRATEGY = new NumberStrategy(Calendar.YEAR) {
         /**
@@ -717,18 +718,25 @@ private static Map<String, Integer> appendDisplayNames(final Calendar calendar,
         return values;
     }
 
+    /**
+     * Clears the cache.
+     */
+    static void clear() {
+        Stream.of(CACHES).filter(Objects::nonNull).forEach(ConcurrentMap::clear);
+    }
+
     /**
      * Gets a cache of Strategies for a particular field
      *
      * @param field The Calendar field
      * @return a cache of Locale to Strategy
      */
     private static ConcurrentMap<Locale, Strategy> getCache(final int field) {
-        synchronized (caches) {
-            if (caches[field] == null) {
-                caches[field] = new ConcurrentHashMap<>(3);
+        synchronized (CACHES) {
+            if (CACHES[field] == null) {
+                CACHES[field] = new ConcurrentHashMap<>(3);
             }
-            return caches[field];
+            return CACHES[field];
         }
     }
 
@@ -786,7 +794,6 @@ private static StringBuilder simpleQuote(final StringBuilder sb, final String va
 
     /** Initialized from Calendar. */
     private transient List<StrategyAndWidth> patterns;
-
     /**
      * Constructs a new FastDateParser.
      *

src/main/java/org/apache/commons/lang3/time/FastDatePrinter.java

@@ -899,8 +899,7 @@ public int estimateLength() {
 
     private static final int MAX_DIGITS = 10; // log10(Integer.MAX_VALUE) ~= 9.3
 
-    private static final ConcurrentMap<TimeZoneDisplayKey, String> cTimeZoneDisplayCache =
-        new ConcurrentHashMap<>(7);
+    private static final ConcurrentMap<TimeZoneDisplayKey, String> timeZoneDisplayCache = new ConcurrentHashMap<>(7);
 
     /**
      * Appends two digits to the given buffer.
@@ -991,6 +990,10 @@ private static void appendFullDigits(final Appendable buffer, int value, int min
         }
     }
 
+    static void clear() {
+        timeZoneDisplayCache.clear();
+    }
+
     /**
      * Gets the time zone display name, using a cache for performance.
      *
@@ -1003,7 +1006,7 @@ private static void appendFullDigits(final Appendable buffer, int value, int min
     static String getTimeZoneDisplay(final TimeZone tz, final boolean daylight, final int style, final Locale locale) {
         final TimeZoneDisplayKey key = new TimeZoneDisplayKey(tz, daylight, style, locale);
         // This is a very slow call, so cache the results.
-        return cTimeZoneDisplayCache.computeIfAbsent(key, k -> tz.getDisplayName(daylight, style, locale));
+        return timeZoneDisplayCache.computeIfAbsent(key, k -> tz.getDisplayName(daylight, style, locale));
     }
 
     /**

src/test/java/org/apache/commons/lang3/time/FastDateParserTest.java

@@ -42,6 +42,8 @@
 import org.apache.commons.lang3.SerializationUtils;
 import org.apache.commons.lang3.SystemUtils;
 import org.apache.commons.lang3.function.TriFunction;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.Arguments;
@@ -50,7 +52,7 @@
 /**
  * Tests {@link org.apache.commons.lang3.time.FastDateParser}.
  */
-public class FastDateParserTest extends AbstractLangTest {
+class FastDateParserTest extends AbstractLangTest {
 
     private enum Expected1806 {
         India(INDIA, "+05", "+0530", "+05:30", true), Greenwich(TimeZones.GMT, "Z", "Z", "Z", false),
@@ -93,6 +95,14 @@ private enum Expected1806 {
 
     private static final Locale SWEDEN = new Locale("sv", "SE");
 
+    @BeforeEach
+    @AfterEach
+    void clear() {
+        AbstractFormatCache.clear();
+        FastDateParser.clear();
+        FastDatePrinter.clear();
+    }
+
     static void checkParse(final Locale locale, final Calendar cal, final SimpleDateFormat simpleDateFormat,
             final DateParser dateParser) {
         final String formattedDate = simpleDateFormat.format(cal.getTime());