DATACMNS-1152 - Setup of ProjectingJackson2HttpMessageConverter now tries to use unique ObjectMapper from ApplicationContext.

We're now trying to look up a uniquely available ObjectMapper instance from the application context falling back to a simple new instance in case none can be found.

src/main/java/org/springframework/data/web/config/SpringDataWebConfiguration.java

@@ -17,8 +17,10 @@ package org.springframework.data.web.config;
 
 import java.util.List;
 import java.util.Optional;
+import java.util.function.Supplier;
 
 import org.springframework.beans.factory.BeanClassLoaderAware;
+import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.beans.factory.ObjectFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Qualifier;
@@ -156,7 +158,9 @@ public class SpringDataWebConfiguration implements WebMvcConfigurer, BeanClassLo
 		if (ClassUtils.isPresent("com.jayway.jsonpath.DocumentContext", context.getClassLoader())
 				&& ClassUtils.isPresent("com.fasterxml.jackson.databind.ObjectMapper", context.getClassLoader())) {
 
-			ProjectingJackson2HttpMessageConverter converter = new ProjectingJackson2HttpMessageConverter(new ObjectMapper());
+			ObjectMapper mapper = getUniqueBean(ObjectMapper.class, context, () -> new ObjectMapper());
+
+			ProjectingJackson2HttpMessageConverter converter = new ProjectingJackson2HttpMessageConverter(mapper);
 			converter.setBeanFactory(context);
 			forwardBeanClassLoader(converter);
 
@@ -193,4 +197,22 @@ public class SpringDataWebConfiguration implements WebMvcConfigurer, BeanClassLo
 			target.setBeanClassLoader(beanClassLoader);
 		}
 	}
+
+	/**
+	 * Returns the uniquely available bean of the given type from the given {@link ApplicationContext} or the one provided
+	 * by the given {@link Supplier} in case the initial lookup fails.
+	 * 
+	 * @param type must not be {@literal null}.
+	 * @param context must not be {@literal null}.
+	 * @param fallback must not be {@literal null}.
+	 * @return
+	 */
+	private static <T> T getUniqueBean(Class<T> type, ApplicationContext context, Supplier<T> fallback) {
+
+		try {
+			return context.getBean(type);
+		} catch (NoSuchBeanDefinitionException o_O) {
+			return fallback.get();
+		}
+	}
 }