Added JaxpVersion

git-svn-id: https://src.springframework.org/svn/spring-framework/trunk@513 50f2f4bb-b051-0410-bef5-90022cba6387

org.springframework.core/src/main/java/org/springframework/util/xml/JaxpVersion.java

@@ -0,0 +1,89 @@
+/*
+ * Copyright 2002-2009 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.util.xml;
+
+import org.springframework.util.ClassUtils;
+
+/**
+ * Helper class used to find the current version of JAXP. We cannot depend on the Java version, since JAXP can be
+ * upgraded independently of the Java version. <p/> Only distinguishes between JAXP 1.0, 1.1, 1.3, and 1.4, since JAXP
+ * 1.2 was a maintenance release with no new classes.
+ *
+ * @author Arjen Poutsma
+ * @since 3.0.0
+ */
+abstract class JaxpVersion {
+
+	public static final int JAXP_10 = 0;
+
+	public static final int JAXP_11 = 1;
+
+	public static final int JAXP_13 = 3;
+
+	public static final int JAXP_14 = 4;
+
+	private static final String JAXP_14_CLASS_NAME = "javax.xml.transform.stax.StAXSource";
+
+	private static int jaxpVersion;
+
+	static {
+		try {
+			ClassUtils.forName(JAXP_14_CLASS_NAME);
+			jaxpVersion = JAXP_14;
+		}
+		catch (ClassNotFoundException ignored) {
+			// default to JAXP 1.3, since Spring 3 requires JDK 1.5
+			jaxpVersion = JAXP_13;
+		}
+	}
+
+	/**
+	 * Gets the JAXP version. This means we can do things like if <code>(getJaxpVersion() < JAXP_13)</code>.
+	 *
+	 * @return a code comparable to the JAXP_XX codes in this class
+	 * @see #JAXP_10
+	 * @see #JAXP_11
+	 * @see #JAXP_13
+	 * @see #JAXP_14
+	 */
+	public static int getJaxpVersion() {
+		return jaxpVersion;
+	}
+
+	/**
+	 * Convenience method to determine if the current JAXP version is at least 1.3 (packaged with JDK 1.5).
+	 *
+	 * @return <code>true</code> if the current JAXP version is at least JAXP 1.3
+	 * @see #getJaxpVersion()
+	 * @see #JAXP_13
+	 */
+	public static boolean isAtLeastJaxp13() {
+		return getJaxpVersion() >= JAXP_13;
+	}
+
+	/**
+	 * Convenience method to determine if the current JAXP version is at least 1.4 (packaged with JDK 1.6).
+	 *
+	 * @return <code>true</code> if the current JAXP version is at least JAXP 1.4
+	 * @see #getJaxpVersion()
+	 * @see #JAXP_14
+	 */
+	public static boolean isAtLeastJaxp14() {
+		return getJaxpVersion() >= JAXP_14;
+	}
+
+}