Moved unit test also to Java.

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/stringOperations.scala

@@ -278,7 +278,7 @@ case class Substring(str: Expression, pos: Expression, len: Expression)
           ba.slice(st, end)
         case s: UTF8String =>
           val (st, end) = slicePos(start, length, () => s.length())
-          s.slice(st, end)
+          s.substring(st, end)
       }
     }
   }

unsafe/src/main/java/org/apache/spark/unsafe/types/UTF8String.java

@@ -99,7 +99,7 @@ public byte[] getBytes() {
    * @param start the position of first code point
    * @param until the position after last code point, exclusive.
    */
-  public UTF8String slice(final int start, final int until) {
+  public UTF8String substring(final int start, final int until) {
     if (until <= start || start >= bytes.length) {
       return UTF8String.fromBytes(new byte[0]);
     }

unsafe/src/test/java/org/apache/spark/unsafe/bitset/BitSetSuite.java

@@ -18,7 +18,6 @@
 package org.apache.spark.unsafe.bitset;
 
 import junit.framework.Assert;
-import org.apache.spark.unsafe.bitset.BitSet;
 import org.junit.Test;
 
 import org.apache.spark.unsafe.memory.MemoryBlock;

unsafe/src/test/java/org/apache/spark/unsafe/types/UTF8StringSuite.java

@@ -0,0 +1,93 @@
+/*
+* 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.
+*/
+
+package org.apache.spark.unsafe.types;
+
+import java.io.UnsupportedEncodingException;
+
+import junit.framework.Assert;
+import org.junit.Test;
+
+public class UTF8StringSuite {
+
+  private void checkBasic(String str, int len) throws UnsupportedEncodingException {
+    Assert.assertEquals(UTF8String.fromString(str).length(), len);
+    Assert.assertEquals(UTF8String.fromBytes(str.getBytes("utf8")).length(), len);
+
+    Assert.assertEquals(UTF8String.fromString(str), str);
+    Assert.assertEquals(UTF8String.fromBytes(str.getBytes("utf8")), str);
+    Assert.assertEquals(UTF8String.fromString(str).toString(), str);
+    Assert.assertEquals(UTF8String.fromBytes(str.getBytes("utf8")).toString(), str);
+    Assert.assertEquals(UTF8String.fromBytes(str.getBytes("utf8")), UTF8String.fromString(str));
+
+    Assert.assertEquals(UTF8String.fromString(str).hashCode(),
+      UTF8String.fromBytes(str.getBytes("utf8")).hashCode());
+  }
+
+  @Test
+  public void basicTest() throws UnsupportedEncodingException {
+    checkBasic("hello", 5);
+    checkBasic("世 界", 3);
+  }
+
+  @Test
+  public void contains() {
+    Assert.assertTrue(UTF8String.fromString("hello").contains(UTF8String.fromString("ello")));
+    Assert.assertFalse(UTF8String.fromString("hello").contains(UTF8String.fromString("vello")));
+    Assert.assertFalse(UTF8String.fromString("hello").contains(UTF8String.fromString("hellooo")));
+    Assert.assertTrue(UTF8String.fromString("大千世界").contains(UTF8String.fromString("千世")));
+    Assert.assertFalse(UTF8String.fromString("大千世界").contains(UTF8String.fromString("世千")));
+    Assert.assertFalse(
+      UTF8String.fromString("大千世界").contains(UTF8String.fromString("大千世界好")));
+  }
+
+  @Test
+  public void startsWith() {
+    Assert.assertTrue(UTF8String.fromString("hello").startsWith(UTF8String.fromString("hell")));
+    Assert.assertFalse(UTF8String.fromString("hello").startsWith(UTF8String.fromString("ell")));
+    Assert.assertFalse(UTF8String.fromString("hello").startsWith(UTF8String.fromString("hellooo")));
+    Assert.assertTrue(UTF8String.fromString("大千世界").startsWith(UTF8String.fromString("大千")));
+    Assert.assertFalse(UTF8String.fromString("大千世界").startsWith(UTF8String.fromString("千")));
+    Assert.assertFalse(
+      UTF8String.fromString("大千世界").startsWith(UTF8String.fromString("大千世界好")));
+  }
+
+  @Test
+  public void endsWith() {
+    Assert.assertTrue(UTF8String.fromString("hello").endsWith(UTF8String.fromString("ello")));
+    Assert.assertFalse(UTF8String.fromString("hello").endsWith(UTF8String.fromString("ellov")));
+    Assert.assertFalse(UTF8String.fromString("hello").endsWith(UTF8String.fromString("hhhello")));
+    Assert.assertTrue(UTF8String.fromString("大千世界").endsWith(UTF8String.fromString("世界")));
+    Assert.assertFalse(UTF8String.fromString("大千世界").endsWith(UTF8String.fromString("世")));
+    Assert.assertFalse(
+      UTF8String.fromString("大千世界").endsWith(UTF8String.fromString("我的大千世界")));
+  }
+
+  @Test
+  public void substring() {
+    Assert.assertEquals(
+      UTF8String.fromString("hello").substring(0, 0), UTF8String.fromString(""));
+    Assert.assertEquals(
+      UTF8String.fromString("hello").substring(1, 3), UTF8String.fromString("el"));
+    Assert.assertEquals(
+      UTF8String.fromString("大千世界").substring(0, 1), UTF8String.fromString("大"));
+    Assert.assertEquals(
+      UTF8String.fromString("大千世界").substring(1, 3), UTF8String.fromString("千世"));
+    Assert.assertEquals(
+      UTF8String.fromString("大千世界").substring(3, 5), UTF8String.fromString("界"));
+  }
+}