Implement an output stream compressing with zstd

1 files changed, 48 insertions, 0 deletions

diff --git a/vespajlib/src/test/java/com/yahoo/compress/ZstdOuputStreamTest.java b/vespajlib/src/test/java/com/yahoo/compress/ZstdOuputStreamTest.java
new file mode 100644
index 00000000000..5d35eb10215
--- /dev/null
+++ b/vespajlib/src/test/java/com/yahoo/compress/ZstdOuputStreamTest.java
@@ -0,0 +1,48 @@
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.compress;
+
+import org.junit.jupiter.api.Test;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+/**
+ * @author bjorncs
+ */
+class ZstdOuputStreamTest {
+
+    @Test
+    void output_stream_compresses_input() throws IOException {
+        byte[] inputData = "The quick brown fox jumps over the lazy dog".getBytes();
+        ByteArrayOutputStream arrayOut = new ByteArrayOutputStream();
+        try (ZstdOuputStream zstdOut = new ZstdOuputStream(arrayOut, 12)) {
+            zstdOut.write(inputData[0]);
+            zstdOut.write(inputData, 1, inputData.length - 1);
+        }
+        byte[] compressedData = arrayOut.toByteArray();
+        ZstdCompressor compressor = new ZstdCompressor();
+        byte[] decompressedData = new byte[inputData.length];
+        compressor.decompress(compressedData, 0, compressedData.length, decompressedData, 0, decompressedData.length);
+        assertArrayEquals(inputData, decompressedData);
+    }
+
+    @Test
+    void compressed_size_is_less_than_uncompressed() throws IOException {
+        StringBuilder builder = new StringBuilder();
+        for (int i = 0; i < 100; i++) {
+            builder.append("The quick brown fox jumps over the lazy dog").append('\n');
+        }
+        byte[] inputData = builder.toString().getBytes();
+        ByteArrayOutputStream arrayOut = new ByteArrayOutputStream();
+        try (ZstdOuputStream zstdOut = new ZstdOuputStream(arrayOut)) {
+            zstdOut.write(inputData);
+        }
+        int compressedSize = arrayOut.toByteArray().length;
+        assertTrue(
+                compressedSize < inputData.length,
+                () -> "Compressed size is " + compressedSize + " while uncompressed size is " + inputData.length);
+    }
+}