Added unit test for compression codecs.

core/src/test/scala/spark/io/CompressionCodecSuite.scala

@@ -0,0 +1,62 @@
+/*
+ * 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 spark.io
+
+import java.io.{ByteArrayInputStream, ByteArrayOutputStream}
+
+import org.scalatest.FunSuite
+
+
+class CompressionCodecSuite extends FunSuite {
+
+  def testCodec(codec: CompressionCodec) {
+    // Write 1000 integers to the output stream, compressed.
+    val outputStream = new ByteArrayOutputStream()
+    val out = codec.compressionOutputStream(outputStream)
+    for (i <- 1 until 1000) {
+      out.write(i % 256)
+    }
+    out.close()
+
+    // Read the 1000 integers back.
+    val inputStream = new ByteArrayInputStream(outputStream.toByteArray)
+    val in = codec.compressionInputStream(inputStream)
+    for (i <- 1 until 1000) {
+      assert(in.read() === i % 256)
+    }
+    in.close()
+  }
+
+  test("default compression codec") {
+    val codec = CompressionCodec.createCodec()
+    assert(codec.getClass === classOf[SnappyCompressionCodec])
+    testCodec(codec)
+  }
+
+  test("lzf compression codec") {
+    val codec = CompressionCodec.createCodec(classOf[LZFCompressionCodec].getName)
+    assert(codec.getClass === classOf[LZFCompressionCodec])
+    testCodec(codec)
+  }
+
+  test("snappy compression codec") {
+    val codec = CompressionCodec.createCodec(classOf[SnappyCompressionCodec].getName)
+    assert(codec.getClass === classOf[SnappyCompressionCodec])
+    testCodec(codec)
+  }
+}