LUCENE-4072: add factory

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1579498 13f79535-47bb-0310-9956-ffa450edef68

lucene/analysis/icu/src/java/org/apache/lucene/analysis/icu/ICUNormalizer2CharFilterFactory.java

@@ -0,0 +1,83 @@
+package org.apache.lucene.analysis.icu;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF 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.
+ */
+
+import java.io.Reader;
+import java.util.Arrays;
+import java.util.Map;
+
+import org.apache.lucene.analysis.util.AbstractAnalysisFactory;
+import org.apache.lucene.analysis.util.CharFilterFactory;
+import org.apache.lucene.analysis.util.MultiTermAwareComponent;
+
+import com.ibm.icu.text.FilteredNormalizer2;
+import com.ibm.icu.text.Normalizer2;
+import com.ibm.icu.text.UnicodeSet;
+
+/**
+ * Factory for {@link ICUNormalizer2CharFilter}
+ * <p>
+ * Supports the following attributes:
+ * <ul>
+ *   <li>name: A <a href="http://unicode.org/reports/tr15/">Unicode Normalization Form</a>, 
+ *       one of 'nfc','nfkc', 'nfkc_cf'. Default is nfkc_cf.
+ *   <li>mode: Either 'compose' or 'decompose'. Default is compose. Use "decompose" with nfc
+ *       or nfkc, to get nfd or nfkd, respectively.
+ *   <li>filter: A {@link UnicodeSet} pattern. Codepoints outside the set are
+ *       always left unchanged. Default is [] (the null set, no filtering).
+ * </ul>
+ * @see ICUNormalizer2CharFilter
+ * @see Normalizer2
+ * @see FilteredNormalizer2
+ */
+public class ICUNormalizer2CharFilterFactory extends CharFilterFactory implements MultiTermAwareComponent {
+  private final Normalizer2 normalizer;
+
+  /** Creates a new ICUNormalizer2CharFilterFactory */
+  public ICUNormalizer2CharFilterFactory(Map<String,String> args) {
+    super(args);
+    String name = get(args, "name", "nfkc_cf");
+    String mode = get(args, "mode", Arrays.asList("compose", "decompose"), "compose");
+    Normalizer2 normalizer = Normalizer2.getInstance
+        (null, name, "compose".equals(mode) ? Normalizer2.Mode.COMPOSE : Normalizer2.Mode.DECOMPOSE);
+    
+    String filter = get(args, "filter");
+    if (filter != null) {
+      UnicodeSet set = new UnicodeSet(filter);
+      if (!set.isEmpty()) {
+        set.freeze();
+        normalizer = new FilteredNormalizer2(normalizer, set);
+      }
+    }
+    if (!args.isEmpty()) {
+      throw new IllegalArgumentException("Unknown parameters: " + args);
+    }
+    this.normalizer = normalizer;
+  }
+
+  @Override
+  public Reader create(Reader input) {
+    return new ICUNormalizer2CharFilter(input, normalizer);
+  }
+
+  @Override
+  public AbstractAnalysisFactory getMultiTermComponent() {
+    return this;
+  }
+  
+}

lucene/analysis/icu/src/resources/META-INF/services/org.apache.lucene.analysis.util.CharFilterFactory

@@ -0,0 +1,16 @@
+#  Licensed to the Apache Software Foundation (ASF) under one or more
+#  contributor license agreements.  See the NOTICE file distributed with
+#  this work for additional information regarding copyright ownership.
+#  The ASF 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.
+
+org.apache.lucene.analysis.icu.ICUNormalizer2CharFilterFactory

lucene/analysis/icu/src/test/org/apache/lucene/analysis/icu/TestICUNormalizer2CharFilterFactory.java

@@ -0,0 +1,52 @@
+package org.apache.lucene.analysis.icu;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF 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.
+ */
+
+import java.io.Reader;
+import java.io.StringReader;
+import java.util.HashMap;
+
+import org.apache.lucene.analysis.BaseTokenStreamTestCase;
+import org.apache.lucene.analysis.TokenStream;
+
+/** basic tests for {@link ICUNormalizer2CharFilterFactory} */
+public class TestICUNormalizer2CharFilterFactory extends BaseTokenStreamTestCase {
+  
+  /** Test nfkc_cf defaults */
+  public void testDefaults() throws Exception {
+    Reader reader = new StringReader("This is a Ｔｅｓｔ");
+    ICUNormalizer2CharFilterFactory factory = new ICUNormalizer2CharFilterFactory(new HashMap<String,String>());
+    reader = factory.create(reader);
+    TokenStream stream = whitespaceMockTokenizer(reader);
+    assertTokenStreamContents(stream, new String[] { "this", "is", "a", "test" });
+  }
+  
+  /** Test that bogus arguments result in exception */
+  public void testBogusArguments() throws Exception {
+    try {
+      new ICUNormalizer2CharFilterFactory(new HashMap<String,String>() {{
+        put("bogusArg", "bogusValue");
+      }});
+      fail();
+    } catch (IllegalArgumentException expected) {
+      assertTrue(expected.getMessage().contains("Unknown parameters"));
+    }
+  }
+  
+  // TODO: add tests for different forms
+}