SpringWebConstraintValidatorFactory for use with validation.xml

Issue: SPR-13327

spring-web/src/main/java/org/springframework/web/bind/support/SpringWebConstraintValidatorFactory.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright 2002-2015 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.web.bind.support;
+
+import javax.validation.ConstraintValidator;
+import javax.validation.ConstraintValidatorFactory;
+
+import org.springframework.web.context.ContextLoader;
+import org.springframework.web.context.WebApplicationContext;
+
+/**
+ * JSR-303 {@link ConstraintValidatorFactory} implementation that delegates to
+ * the current Spring {@link WebApplicationContext} for creating autowired
+ * {@link ConstraintValidator} instances.
+ *
+ * <p>In contrast to
+ * {@link org.springframework.validation.beanvalidation.SpringConstraintValidatorFactory},
+ * this variant is meant for declarative use in a standard {@code validation.xml} file,
+ * e.g. in combination with JAX-RS or JAX-WS.
+ *
+ * @author Juergen Hoeller
+ * @since 4.2.1
+ * @see ContextLoader#getCurrentWebApplicationContext()
+ * @see org.springframework.validation.beanvalidation.SpringConstraintValidatorFactory
+ */
+public class SpringWebConstraintValidatorFactory implements ConstraintValidatorFactory {
+
+	@Override
+	public <T extends ConstraintValidator<?, ?>> T getInstance(Class<T> key) {
+		return getWebApplicationContext().getAutowireCapableBeanFactory().createBean(key);
+	}
+
+	// Bean Validation 1.1 releaseInstance method
+	public void releaseInstance(ConstraintValidator<?, ?> instance) {
+		getWebApplicationContext().getAutowireCapableBeanFactory().destroyBean(instance);
+	}
+
+
+	/**
+	 * Retrieve the Spring {@link WebApplicationContext} to use.
+	 * The default implementation returns the current {@link WebApplicationContext}
+	 * as registered for the thread context class loader.
+	 * @return the current WebApplicationContext (never {@code null})
+	 * @see ContextLoader#getCurrentWebApplicationContext()
+	 */
+	protected WebApplicationContext getWebApplicationContext() {
+		WebApplicationContext wac = ContextLoader.getCurrentWebApplicationContext();
+		if (wac == null) {
+			throw new IllegalStateException("No WebApplicationContext registered for current thread - " +
+					"consider overriding SpringWebConstraintValidatorFactory.getWebApplicationContext()");
+		}
+		return wac;
+	}
+
+}