1 files changed, 86 insertions, 0 deletions
diff --git a/vespajlib/src/main/java/com/yahoo/io/Blob.java b/vespajlib/src/main/java/com/yahoo/io/Blob.java
new file mode 100644
index 00000000000..808371e7b58
--- /dev/null
+++ b/vespajlib/src/main/java/com/yahoo/io/Blob.java
@@ -0,0 +1,86 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.io;
+
+import java.nio.ByteBuffer;
+
+/**
+ * A Blob contains opaque data in the form of a byte array.
+ **/
+public class Blob {
+
+    /**
+     * Shared empty array.
+     **/
+    private static byte[] empty = new byte[0];
+
+    /**
+     * Internal data, will never be 'null'.
+     **/
+    private byte[] data;
+
+    /**
+     * Create a Blob containing an empty byte array.
+     **/
+    public Blob() {
+        data = empty;
+    }
+
+    /**
+     * Create a Blob containg a copy of a subset of the given byte
+     * array.
+     **/
+    public Blob(byte[] src, int offset, int length) {
+        data = new byte[length];
+        System.arraycopy(src, offset, data, 0, length);
+    }
+
+    /**
+     * Create a Blob containing a copy of the given byte array.
+     **/
+    public Blob(byte[] src) {
+        this(src, 0, src.length);
+    }
+
+    /**
+     * Create a Blob containing a copy of the data held by the given
+     * blob.
+     **/
+    public Blob(Blob src) {
+        this(src.data);
+    }
+
+    /**
+     * Create a Blob containing a number of bytes read from a byte
+     * buffer.
+     **/
+    public Blob(ByteBuffer src, int length) {
+        data = new byte[length];
+        src.get(data);
+    }
+
+    /**
+     * Create a Blob containing all bytes that could be read from a
+     * byte buffer.
+     **/
+    public Blob(ByteBuffer src) {
+        this(src, src.remaining());
+    }
+
+    /**
+     * Obtain the internal data held by this object.
+     *
+     * @return internal data
+     **/
+    public byte[] get() {
+        return data;
+    }
+
+    /**
+     * Write the data held by this object to the given byte buffer.
+     *
+     * @param dst where to write the contained data
+     **/
+    public void write(ByteBuffer dst) {
+        dst.put(data);
+    }
+}