Use random input for multipart payload test

src/test/java/org/gaul/s3proxy/S3ProxyTest.java

@@ -404,8 +404,8 @@ public final class S3ProxyTest {
         MultipartUpload mpu = s3BlobStore.initiateMultipartUpload(
                 containerName, blobMetadata);
 
-        ByteSource byteSource = ByteSource.wrap(
+        ByteSource byteSource = TestUtils.randomByteSource().slice(
-                new byte[(int) blobStore.getMinimumMultipartPartSize() + 1]);
+                0, blobStore.getMinimumMultipartPartSize() + 1);
         ByteSource byteSource1 = byteSource.slice(
                 0, blobStore.getMinimumMultipartPartSize());
         ByteSource byteSource2 = byteSource.slice(

src/test/java/org/gaul/s3proxy/TestUtils.java

@@ -0,0 +1,87 @@
+/*
+ * Copyright 2014-2015 Andrew Gaul <andrew@gaul.org>
+ *
+ * Licensed 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.gaul.s3proxy;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Random;
+
+import com.google.common.io.ByteSource;
+
+final class TestUtils {
+    private TestUtils() {
+        throw new AssertionError("intentionally unimplemented");
+    }
+
+    static ByteSource randomByteSource() {
+        return randomByteSource(0);
+    }
+
+    static ByteSource randomByteSource(long seed) {
+        return new RandomByteSource(seed);
+    }
+
+    private static class RandomByteSource extends ByteSource {
+        private final long seed;
+
+        RandomByteSource(long seed) {
+            this.seed = seed;
+        }
+
+        @Override
+        public InputStream openStream() {
+            return new RandomInputStream(seed);
+        }
+    }
+
+    private static class RandomInputStream extends InputStream {
+        private final Random random;
+        private boolean closed;
+
+        RandomInputStream(long seed) {
+            this.random = new Random(seed);
+        }
+
+        @Override
+        public synchronized int read() throws IOException {
+            if (closed) {
+                throw new IOException("Stream already closed");
+            }
+            return (byte) random.nextInt();
+        }
+
+        @Override
+        public synchronized int read(byte[] b) throws IOException {
+            return read(b, 0, b.length);
+        }
+
+        @Override
+        public synchronized int read(byte[] b, int off, int len)
+                throws IOException {
+            for (int i = 0; i < len; ++i) {
+                b[off + i] = (byte) read();
+            }
+            return len;
+        }
+
+        @Override
+        public void close() throws IOException {
+            super.close();
+            closed = true;
+        }
+    }
+}