root
/
spring-framework
mirror of https://github.com/spring-projects/spring-framework.git
1
0
Fork 0
Code Issues Actions 8 Packages Projects Releases Wiki Activity

Consistent data class constructor resolution with clear error message 

MVC data class processor constructs target instance even in case of binding failure, as long as the corresponding method parameter is not marked as optional.

Closes gh-24372
This commit is contained in:
Juergen Hoeller 2020-09-01 19:10:32 +02:00
parent 278c6d5cdb
commit e20bff9c64
5 changed files with 93 additions and 49 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
spring-beans/src/main/java/org/springframework/beans/BeanUtils.java
View File

@ -226,6 +226,35 @@ public abstract class BeanUtils {
}
}
/**
* Return a resolvable constructor for the provided class, either a primary constructor
* or single public constructor or simply a default constructor. Callers have to be
* prepared to resolve arguments for the returned constructor's parameters, if any.
* @param clazz the class to check
* @since 5.3
* @see #findPrimaryConstructor
*/
@SuppressWarnings("unchecked")
public static <T> Constructor<T> getResolvableConstructor(Class<T> clazz) {
Constructor<T> ctor = findPrimaryConstructor(clazz);
if (ctor == null) {
Constructor<?>[] ctors = clazz.getConstructors();
if (ctors.length == 1) {
ctor = (Constructor<T>) ctors[0];
}
else {
try {
ctor = clazz.getDeclaredConstructor();
}
catch (NoSuchMethodException ex) {
throw new IllegalStateException("No primary or single public constructor found for " +
clazz + " - and no default constructor found either");
}
}
}
return ctor;
}
/**
* Return the primary constructor of the provided class. For Kotlin classes, this
* returns the Java constructor corresponding to the Kotlin primary constructor

18
spring-jdbc/src/main/java/org/springframework/jdbc/core/DataClassRowMapper.java
View File

@ -79,23 +79,7 @@ public class DataClassRowMapper<T> extends BeanPropertyRowMapper<T> {
protected void initialize(Class<T> mappedClass) {
super.initialize(mappedClass);
this.mappedConstructor = BeanUtils.findPrimaryConstructor(mappedClass);
if (this.mappedConstructor == null) {
Constructor<?>[] ctors = mappedClass.getConstructors();
if (ctors.length == 1) {
this.mappedConstructor = (Constructor<T>) ctors[0];
}
else {
try {
this.mappedConstructor = mappedClass.getDeclaredConstructor();
}
catch (NoSuchMethodException ex) {
throw new IllegalStateException("No primary or default constructor found for " + mappedClass, ex);
}
}
}
this.mappedConstructor = BeanUtils.getResolvableConstructor(mappedClass);
if (this.mappedConstructor.getParameterCount() > 0) {
this.constructorParameterNames = BeanUtils.getParameterNames(this.mappedConstructor);
this.constructorParameterTypes = this.mappedConstructor.getParameterTypes();

38
spring-web/src/main/java/org/springframework/web/method/annotation/ModelAttributeMethodProcessor.java
View File

@ -33,6 +33,7 @@ import javax.servlet.http.Part;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.BeanInstantiationException;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.TypeMismatchException;
import org.springframework.core.MethodParameter;
@ -149,6 +150,9 @@ public class ModelAttributeMethodProcessor implements HandlerMethodArgumentResol
if (parameter.getParameterType() == Optional.class) {
attribute = Optional.empty();
}
else {
attribute = ex.getTarget();
}
bindingResult = ex.getBindingResult();
}
}
@ -207,22 +211,7 @@ public class ModelAttributeMethodProcessor implements HandlerMethodArgumentResol
MethodParameter nestedParameter = parameter.nestedIfOptional();
Class<?> clazz = nestedParameter.getNestedParameterType();
Constructor<?> ctor = BeanUtils.findPrimaryConstructor(clazz);
if (ctor == null) {
Constructor<?>[] ctors = clazz.getConstructors();
if (ctors.length == 1) {
ctor = ctors[0];
}
else {
try {
ctor = clazz.getDeclaredConstructor();
}
catch (NoSuchMethodException ex) {
throw new IllegalStateException("No primary or default constructor found for " + clazz, ex);
}
}
}
Constructor<?> ctor = BeanUtils.getResolvableConstructor(clazz);
Object attribute = constructAttribute(ctor, attributeName, parameter, binderFactory, webRequest);
if (parameter != nestedParameter) {
attribute = Optional.of(attribute);
@ -244,6 +233,7 @@ public class ModelAttributeMethodProcessor implements HandlerMethodArgumentResol
* @throws Exception in case of constructor invocation failure
* @since 5.1
*/
@SuppressWarnings("serial")
protected Object constructAttribute(Constructor<?> ctor, String attributeName, MethodParameter parameter,
WebDataBinderFactory binderFactory, NativeWebRequest webRequest) throws Exception {
@ -290,7 +280,7 @@ public class ModelAttributeMethodProcessor implements HandlerMethodArgumentResol
}
catch (TypeMismatchException ex) {
ex.initPropertyName(paramName);
args[i] = value;
args[i] = null;
failedParams.add(paramName);
binder.getBindingResult().recordFieldValue(paramName, paramType, value);
binder.getBindingErrorProcessor().processPropertyAccessException(ex, binder.getBindingResult());
@ -308,6 +298,20 @@ public class ModelAttributeMethodProcessor implements HandlerMethodArgumentResol
validateValueIfApplicable(binder, parameter, ctor.getDeclaringClass(), paramName, value);
}
}
if (!parameter.isOptional()) {
try {
Object target = BeanUtils.instantiateClass(ctor, args);
throw new BindException(result) {
@Override
public Object getTarget() {
return target;
}
};
}
catch (BeanInstantiationException ex) {
// swallow and proceed without target instance
}
}
throw new BindException(result);
}

16
spring-webflux/src/main/java/org/springframework/web/reactive/result/method/annotation/ModelAttributeMethodArgumentResolver.java
View File

@ -201,21 +201,7 @@ public class ModelAttributeMethodArgumentResolver extends HandlerMethodArgumentR
private Mono<?> createAttribute(
String attributeName, Class<?> clazz, BindingContext context, ServerWebExchange exchange) {
Constructor<?> ctor = BeanUtils.findPrimaryConstructor(clazz);
if (ctor == null) {
Constructor<?>[] ctors = clazz.getConstructors();
if (ctors.length == 1) {
ctor = ctors[0];
}
else {
try {
ctor = clazz.getDeclaredConstructor();
}
catch (NoSuchMethodException ex) {
throw new IllegalStateException("No primary or default constructor found for " + clazz, ex);
}
}
}
Constructor<?> ctor = BeanUtils.getResolvableConstructor(clazz);
return constructAttribute(ctor, attributeName, context, exchange);
}

41
spring-webmvc/src/test/java/org/springframework/web/servlet/mvc/method/annotation/ServletAnnotationControllerHandlerMethodTests.java
View File

@ -2060,6 +2060,31 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
assertThat(response.getContentAsString()).isEqualTo("2:null-x-null");
}
@PathPatternsParameterizedTest
void dataClassBindingWithNullable(boolean usePathPatterns) throws Exception {
initDispatcherServlet(NullableDataClassController.class, usePathPatterns);
MockHttpServletRequest request = new MockHttpServletRequest("GET", "/bind");
request.addParameter("param1", "value1");
request.addParameter("param2", "true");
request.addParameter("param3", "3");
MockHttpServletResponse response = new MockHttpServletResponse();
getServlet().service(request, response);
assertThat(response.getContentAsString()).isEqualTo("value1-true-3");
}
@PathPatternsParameterizedTest
void dataClassBindingWithNullableAndConversionError(boolean usePathPatterns) throws Exception {
initDispatcherServlet(NullableDataClassController.class, usePathPatterns);
MockHttpServletRequest request = new MockHttpServletRequest("GET", "/bind");
request.addParameter("param1", "value1");
request.addParameter("param2", "x");
MockHttpServletResponse response = new MockHttpServletResponse();
getServlet().service(request, response);
assertThat(response.getContentAsString()).isEqualTo("value1-x-null");
}
@PathPatternsParameterizedTest
void dataClassBindingWithOptional(boolean usePathPatterns) throws Exception {
initDispatcherServlet(OptionalDataClassController.class, usePathPatterns);
@ -3895,6 +3920,7 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
@RequestMapping("/bind")
public BindStatusView handle(@Valid DataClass data, BindingResult result) {
assertThat(data).isNotNull();
if (result.hasErrors()) {
return new BindStatusView(result.getErrorCount() + ":" + result.getFieldValue("param1") + "-" +
result.getFieldValue("param2") + "-" + result.getFieldValue("param3"));
@ -3987,6 +4013,21 @@ public class ServletAnnotationControllerHandlerMethodTests extends AbstractServl
}
}
@RestController
public static class NullableDataClassController {
@RequestMapping("/bind")
public String handle(@Nullable DataClass data, BindingResult result) {
if (result.hasErrors()) {
assertThat(data).isNull();
return result.getFieldValue("param1") + "-" + result.getFieldValue("param2") + "-" +
result.getFieldValue("param3");
}
assertThat(data).isNotNull();
return data.param1 + "-" + data.param2 + "-" + data.param3;
}
}
@RestController
public static class OptionalDataClassController {