GUACAMOLE-1218: Refactor guacamole-auth-json's ByteArrayProperty into guacamole-ext.

guacamole-ext/src/main/java/org/apache/guacamole/properties/ByteArrayProperty.java

@@ -0,0 +1,52 @@
+/*
+ * 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.guacamole.properties;
+
+import javax.xml.bind.DatatypeConverter;
+import org.apache.guacamole.GuacamoleException;
+import org.apache.guacamole.GuacamoleServerException;
+
+/**
+ * A GuacamoleProperty whose value is a byte array. The bytes of the byte array
+ * must be represented as a hexadecimal string within the property value. The
+ * hexadecimal string is case-insensitive.
+ */
+public abstract class ByteArrayProperty implements GuacamoleProperty<byte[]> {
+
+    @Override
+    public byte[] parseValue(String value) throws GuacamoleException {
+
+        // If no property provided, return null.
+        if (value == null)
+            return null;
+
+        // Return value parsed from hex
+        try {
+            return DatatypeConverter.parseHexBinary(value);
+        }
+
+        // Fail parse if hex invalid
+        catch (IllegalArgumentException e) {
+            throw new GuacamoleServerException("Invalid hexadecimal value.", e);
+        }
+
+    }
+
+}