add compressed string

.idea/dictionaries/kimchy.xml

@@ -32,6 +32,7 @@
       <w>configurator</w>
       <w>coord</w>
       <w>cpus</w>
+      <w>cstr</w>
       <w>datagram</w>
       <w>datas</w>
       <w>deque</w>

modules/elasticsearch/src/main/java/org/elasticsearch/common/compress/CompressedString.java

@@ -0,0 +1,77 @@
+/*
+ * Licensed to Elastic Search and Shay Banon under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. Elastic Search 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.common.compress;
+
+import org.apache.lucene.util.UnicodeUtil;
+import org.elasticsearch.common.Unicode;
+import org.elasticsearch.common.compress.lzf.LZFDecoder;
+import org.elasticsearch.common.compress.lzf.LZFEncoder;
+import org.elasticsearch.common.io.stream.StreamInput;
+import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.common.io.stream.Streamable;
+
+import java.io.IOException;
+import java.util.Arrays;
+
+/**
+ * @author kimchy (shay.banon)
+ */
+public class CompressedString implements Streamable {
+
+    private byte[] bytes;
+
+    public CompressedString(String str) throws IOException {
+        UnicodeUtil.UTF8Result result = Unicode.unsafeFromStringAsUtf8(str);
+        this.bytes = LZFEncoder.encodeWithCache(result.result, result.length);
+    }
+
+    public byte[] bytes() {
+        return this.bytes;
+    }
+
+    public String string() throws IOException {
+        return Unicode.fromBytes(LZFDecoder.decode(bytes));
+    }
+
+    @Override public void readFrom(StreamInput in) throws IOException {
+        bytes = new byte[in.readVInt()];
+        in.readBytes(bytes, 0, bytes.length);
+    }
+
+    @Override public void writeTo(StreamOutput out) throws IOException {
+        out.writeVInt(bytes.length);
+        out.writeBytes(bytes);
+    }
+
+    @Override public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+
+        CompressedString that = (CompressedString) o;
+
+        if (!Arrays.equals(bytes, that.bytes)) return false;
+
+        return true;
+    }
+
+    @Override public int hashCode() {
+        return bytes != null ? Arrays.hashCode(bytes) : 0;
+    }
+}

modules/elasticsearch/src/test/java/org/elasticsearch/common/compress/CompressedStringTests.java

@@ -0,0 +1,40 @@
+/*
+ * Licensed to Elastic Search and Shay Banon under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. Elastic Search 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.common.compress;
+
+import org.testng.annotations.Test;
+
+import java.io.IOException;
+
+import static org.hamcrest.MatcherAssert.*;
+import static org.hamcrest.Matchers.*;
+
+/**
+ * @author kimchy (shay.banon)
+ */
+public class CompressedStringTests {
+
+    @Test public void simpleTests() throws IOException {
+        String str = "this is a simple string";
+        CompressedString cstr = new CompressedString(str);
+        assertThat(cstr.string(), equalTo(str));
+        assertThat(new CompressedString(str), equalTo(cstr));
+    }
+}