[New] Added DBC class for helping in assertions

src/main/java/ch/eitchnet/utils/dbc/DBC.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2013 Robert von Burg <eitch@eitchnet.ch>
+ * 
+ * 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 ch.eitchnet.utils.dbc;
+
+import java.text.MessageFormat;
+
+import ch.eitchnet.utils.helper.StringHelper;
+
+/**
+ * @author Robert von Burg <eitch@eitchnet.ch>
+ */
+public enum DBC {
+
+	PRE {
+		public void assertNotEmpty(String msg, String value) {
+			if (StringHelper.isEmpty(value)) {
+				String ex = "Illegal empty value: {0}"; //$NON-NLS-1$
+				ex = MessageFormat.format(ex, msg);
+				throw new DbcException(ex);
+			}
+		}
+
+		@Override
+		public void assertNotNull(String msg, Object value) {
+			if (value == null) {
+				String ex = "Illegal null value: {0}"; //$NON-NLS-1$
+				ex = MessageFormat.format(ex, msg);
+				throw new DbcException(ex);
+			}
+		}
+	};
+
+	public abstract void assertNotEmpty(String msg, String value);
+	public abstract void assertNotNull(String msg, Object value);
+
+	public class DbcException extends RuntimeException {
+		private static final long serialVersionUID = 1L;
+
+		public DbcException(String message) {
+			super(message);
+		}
+	}
+}