Added UNICODE_CHARACTER_CLASS support to Regex flags. This flag is only supported in Java7 and is ignored if set on a java 6 JVM

Closes #2895

src/main/java/org/elasticsearch/common/regex/Regex.java

@@ -22,6 +22,7 @@ package org.elasticsearch.common.regex;
 import org.elasticsearch.ElasticSearchIllegalArgumentException;
 import org.elasticsearch.common.Strings;
 
+import java.util.Locale;
 import java.util.regex.Pattern;
 
 /**
@@ -29,6 +30,13 @@ import java.util.regex.Pattern;
  */
 public class Regex {
     
+    /**
+     * This Regex / {@link Pattern} flag is supported from Java 7 on.
+     * If set on a Java6 JVM the flag will be ignored.
+     * 
+     */
+    public static final int UNICODE_CHARACTER_CLASS = 0x100; // supported in JAVA7
+
     /**
      * Is the str a simple match pattern.
      */
@@ -107,22 +115,25 @@ public class Regex {
             if (s.isEmpty()) {
                 continue;
             }
-            if ("CASE_INSENSITIVE".equalsIgnoreCase(s)) {
+            s = s.toUpperCase(Locale.ROOT);
+            if ("CASE_INSENSITIVE".equals(s)) {
                 pFlags |= Pattern.CASE_INSENSITIVE;
-            } else if ("MULTILINE".equalsIgnoreCase(s)) {
+            } else if ("MULTILINE".equals(s)) {
                 pFlags |= Pattern.MULTILINE;
-            } else if ("DOTALL".equalsIgnoreCase(s)) {
+            } else if ("DOTALL".equals(s)) {
                 pFlags |= Pattern.DOTALL;
-            } else if ("UNICODE_CASE".equalsIgnoreCase(s)) {
+            } else if ("UNICODE_CASE".equals(s)) {
                 pFlags |= Pattern.UNICODE_CASE;
-            } else if ("CANON_EQ".equalsIgnoreCase(s)) {
+            } else if ("CANON_EQ".equals(s)) {
                 pFlags |= Pattern.CANON_EQ;
-            } else if ("UNIX_LINES".equalsIgnoreCase(s)) {
+            } else if ("UNIX_LINES".equals(s)) {
                 pFlags |= Pattern.UNIX_LINES;
-            } else if ("LITERAL".equalsIgnoreCase(s)) {
+            } else if ("LITERAL".equals(s)) {
                 pFlags |= Pattern.LITERAL;
-            } else if ("COMMENTS".equalsIgnoreCase(s)) {
+            } else if ("COMMENTS".equals(s)) {
                 pFlags |= Pattern.COMMENTS;
+            } else if ("UNICODE_CHAR_CLASS".equals(s)) {
+                pFlags |= UNICODE_CHARACTER_CLASS;
             } else {
                 throw new ElasticSearchIllegalArgumentException("Unknown regex flag [" + s + "]");
             }
@@ -156,6 +167,9 @@ public class Regex {
         if ((flags & Pattern.COMMENTS) != 0) {
             sb.append("COMMENTS|");
         } 
+        if ((flags & UNICODE_CHARACTER_CLASS) != 0) {
+            sb.append("UNICODE_CHAR_CLASS|");
+        }
         return sb.toString();
     }
 }

src/test/java/org/elasticsearch/test/unit/common/regex/RegexTests.java

@@ -0,0 +1,58 @@
+/*
+ * Licensed to ElasticSearch and Shay Banon under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. ElasticSearch licenses this
+ * file to you 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.elasticsearch.test.unit.common.regex;
+
+import java.util.Random;
+import java.util.regex.Pattern;
+
+import org.elasticsearch.common.regex.Regex;
+import org.testng.annotations.Test;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.equalTo;
+public class RegexTests {
+
+    @Test
+    public void testFlags() {
+        String[] supportedFlags = new String[] { "CASE_INSENSITIVE", "MULTILINE", "DOTALL", "UNICODE_CASE", "CANON_EQ", "UNIX_LINES",
+                "LITERAL", "COMMENTS", "UNICODE_CHAR_CLASS" };
+        int[] flags = new int[] { Pattern.CASE_INSENSITIVE, Pattern.MULTILINE, Pattern.DOTALL, Pattern.UNICODE_CASE, Pattern.CANON_EQ,
+                Pattern.UNIX_LINES, Pattern.LITERAL, Pattern.COMMENTS, Regex.UNICODE_CHARACTER_CLASS };
+        long seed = System.currentTimeMillis();
+        Random random = new Random(seed);
+        int num = 10 + random.nextInt(100);
+        for (int i = 0; i < num; i++) {
+            int numFlags = random.nextInt(flags.length+1);
+            int current = 0;
+            StringBuilder builder = new StringBuilder();
+            for (int j = 0; j < numFlags; j++) {
+                int index = random.nextInt(flags.length);
+                current |= flags[index];
+                builder.append(supportedFlags[index]);
+                if (j < numFlags-1) {
+                    builder.append("|");
+                }
+            }
+            String flagsToString = Regex.flagsToString(current);
+            assertThat(Regex.flagsFromString(builder.toString()), equalTo(current));
+            assertThat(Regex.flagsFromString(builder.toString()), equalTo(Regex.flagsFromString(flagsToString)));
+            Pattern.compile("\\w\\d{1,2}", current); // accepts the flags?
+        }
+    }
+}