#137 - Extracted TemplateVariable into separate class.

TempalteVariable is now a standalone class. Introduced TempalteVariables wrapper to allow easy collecting of TempalteVariable instances and rendering them in the shortest possible way.

src/main/java/org/springframework/hateoas/TemplateVariables.java

@@ -0,0 +1,131 @@
+/*
+ * Copyright 2014 the original author or authors.
+ *
+ * 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.springframework.hateoas;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.List;
+
+import org.springframework.util.Assert;
+
+/**
+ * Wrapper type for a collection of {@link TemplateVariable}.
+ * 
+ * @author Oliver Gierke
+ */
+public class TemplateVariables implements Iterable<TemplateVariable> {
+
+	public static TemplateVariables NONE = new TemplateVariables(Collections.<TemplateVariable> emptyList());
+
+	private final List<TemplateVariable> variables;
+
+	/**
+	 * Creates a new {@link TemplateVariables} for the given {@link TemplateVariable}s.
+	 * 
+	 * @param variables must not be {@literal null}.
+	 */
+	public TemplateVariables(TemplateVariable... variables) {
+		this(Arrays.asList(variables));
+	}
+
+	/**
+	 * Creates a new {@link TemplateVariables} for the given {@link TemplateVariable}s.
+	 * 
+	 * @param variables must not be {@literal null}.
+	 */
+	public TemplateVariables(List<TemplateVariable> variables) {
+
+		Assert.notNull(variables, "Template variables must not be null!");
+		this.variables = Collections.unmodifiableList(variables);
+	}
+
+	/**
+	 * Concatenates the given {@link TemplateVariable}s to the current one.
+	 * 
+	 * @param variables must not be {@literal null}.
+	 * @return
+	 */
+	public TemplateVariables concat(TemplateVariable... variables) {
+		return concat(Arrays.asList(variables));
+	}
+
+	/**
+	 * Concatenates the given {@link TemplateVariable}s to the current one.
+	 * 
+	 * @param variables must not be {@literal null}.
+	 * @return
+	 */
+	public TemplateVariables concat(Collection<TemplateVariable> variables) {
+
+		List<TemplateVariable> result = new ArrayList<TemplateVariable>(this.variables.size() + variables.size());
+		result.addAll(this.variables);
+		result.addAll(variables);
+
+		return new TemplateVariables(result);
+	}
+
+	/**
+	 * Concatenates the given {@link TemplateVariables} to the current one.
+	 * 
+	 * @param variables must not be {@literal null}.
+	 * @return
+	 */
+	public TemplateVariables concat(TemplateVariables variables) {
+		return concat(variables.variables);
+	}
+
+	/* 
+	 * (non-Javadoc)
+	 * @see java.lang.Iterable#iterator()
+	 */
+	@Override
+	public Iterator<TemplateVariable> iterator() {
+		return this.variables.iterator();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see java.lang.Object#toString()
+	 */
+	public String toString() {
+
+		if (variables.isEmpty()) {
+			return "";
+		}
+
+		StringBuilder builder = new StringBuilder();
+		TemplateVariable previous = null;
+
+		for (TemplateVariable variable : variables) {
+
+			if (previous == null) {
+				builder.append("{").append(variable.getType().toString());
+			} else if (!previous.isOfSameTypeAs(variable)) {
+				builder.append("}{").append(variable.getType().toString());
+			} else {
+				builder.append(",");
+			}
+
+			previous = variable;
+			builder.append(variable.getName());
+		}
+
+		return builder.append("}").toString();
+	}
+}