老鸟就别看了，嘿嘿。。。。当然你要实在要看我也木有办法
Spring mvc 默认 不支持json 字符串 接收参数 （例如自动将json转为自定义对象，基本数据类型等等，这样还要自己去解析，每个都这样工作量还是比较大的）
由于Spring的一些限制，只能使用注解的方式来代替默认的@RequestParam （该参数是只支持标准的表单数据）
注：本实现方式不支持 @Valid 注解，介意就别耽搁时间了，好了，不废话，来代码，最直观
Step 1:添加自定义的注解###
代码：
import org.springframework.web.bind.annotation.ValueConstants;
import java.lang.annotation.*;
@Target(ElementType.PARAMETER)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface RequestCustomParam {
/**
* The name of the request parameter to bind to.
*/
String value() default "";
/**
* Whether the parameter is required.
* <p>Default is {@code true}, leading to an exception thrown in case
* of the parameter missing in the request. Switch this to {@code false}
* if you prefer a {@code null} in case of the parameter missing.
* <p>Alternatively, provide a {@link #defaultValue() defaultValue},
* which implicitly sets this flag to {@code false}.
*/
boolean required() default true;
/**
* The default value to use as a fallback when the request parameter value
* is not provided or empty. Supplying a default value implicitly sets
* {@link #required()} to false.
*/
String defaultValue() default ValueConstants.DEFAULT_NONE;
}
Step2 自定义的参数解析器###
（部分代码是从spring-web包中的org.springframework.web.method.annotation.ModelAttributeMethodProcessor 和RequestParamMethodArgumentResolver中拷贝出来，为了同时支持正常的表单提交（@modelAttribute @RequestParam注解）;）
import com.alibaba.fastjson.JSONObject;
import com.boh.api.Exception.UnauthenticatedException;
import com.boh.api.argument.annotation.RequestCustomParam;
import com.boh.api.common.SpringUtils;
import com.boh.common.enums.ErrorCode;
import com.boh.core.dto.BatchDto;
import org.apache.commons.beanutils.ConvertUtils;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.config.BeanExpressionContext;
import org.springframework.beans.factory.config.BeanExpressionResolver;
import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.core.GenericCollectionTypeResolver;
import org.springframework.core.MethodParameter;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.core.convert.ConversionService;
import org.springframework.core.convert.TypeDescriptor;
import org.springframework.util.Assert;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
import org.springframework.util.StringUtils;
import org.springframework.validation.BindException;
import org.springframework.validation.Errors;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.MissingServletRequestParameterException;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.annotation.RequestPart;
import org.springframework.web.bind.annotation.ValueConstants;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.context.request.RequestScope;
import org.springframework.web.method.annotation.ModelFactory;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.method.support.ModelAndViewContainer;
import org.springframework.web.multipart.MultipartException;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.MultipartHttpServletRequest;
import org.springframework.web.servlet.mvc.method.annotation.ExtendedServletRequestDataBinder;
import org.springframework.web.util.UriComponentsBuilder;
import org.springframework.web.util.WebUtils;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.Part;
import java.io.BufferedReader;
import java.lang.annotation.Annotation;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;
public class CustomMethodArgumentResolver implements HandlerMethodArgumentResolver {
private static String requestBodyCache = "";
private static final TypeDescriptor STRING_TYPE_DESCRIPTOR = TypeDescriptor.valueOf(String.class);
private final boolean annotationNotRequired;
private final ConfigurableBeanFactory configurableBeanFactory;
private final BeanExpressionContext expressionContext;
private final boolean useDefaultResolution;
private Map<MethodParameter, NamedValueInfo> namedValueInfoCache = new ConcurrentHashMap<MethodParameter, NamedValueInfo>(256);
public CustomMethodArgumentResolver(ConfigurableBeanFactory beanFactory) {
this.configurableBeanFactory = beanFactory;
this.expressionContext = (beanFactory != null ? new BeanExpressionContext(beanFactory, new RequestScope()) : null);
this.annotationNotRequired=true;
this.useDefaultResolution = false;
}
public CustomMethodArgumentResolver() {
this.annotationNotRequired=true;
this.useDefaultResolution = false;
this.configurableBeanFactory = null;
this.expressionContext = null;
}
@Override
public boolean supportsParameter(MethodParameter parameter) {
Class<?> paramType = parameter.getParameterType();
if (parameter.hasParameterAnnotation(RequestCustomParam.class)) {
return true;
} else {
if (parameter.hasParameterAnnotation(RequestPart.class)) {
return false;
}
else if (MultipartFile.class.equals(paramType) || "javax.servlet.http.Part".equals(paramType.getName())) {
return true;
} else
return this.useDefaultResolution && BeanUtils.isSimpleProperty(paramType);
}
}
@Override
public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer, NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {
HttpServletRequest servletRequest = webRequest.getNativeRequest(HttpServletRequest.class);
String content=servletRequest.getContentType();
//如果请求类型是application/json ，则调用fastjson 去解析
if (servletRequest.getContentType().contains("application/json")) {
return bindRequestParameters( parameter, servletRequest);
} else {
Class<?> parameterType = parameter.getParameterType();
if (BeanUtils.isSimpleProperty(parameterType)) {
//如果是Map对象，调用resolveMapArgument方法
if (Map.class.isAssignableFrom(parameter.getParameterType())) {
return resolveMapArgument(parameter,mavContainer,webRequest,binderFactory);
}
Class<?> paramType = parameter.getParameterType();
NamedValueInfo namedValueInfo = getNamedValueInfo(parameter);
Object arg = resolveName(namedValueInfo.name, parameter, webRequest);
if (arg == null) {
if (namedValueInfo.defaultValue != null) {
arg = resolveDefaultValue(namedValueInfo.defaultValue);
}
else if (namedValueInfo.required && !parameter.getParameterType().getName().equals("java.util.Optional")) {
handleMissingValue(namedValueInfo.name, parameter);
}
arg = handleNullValue(namedValueInfo.name, arg, paramType);
}
else if ("".equals(arg) && namedValueInfo.defaultValue != null) {
arg = resolveDefaultValue(namedValueInfo.defaultValue);
}
if (binderFactory != null) {
WebDataBinder binder = binderFactory.createBinder(webRequest, null, namedValueInfo.name);
arg = binder.convertIfNecessary(arg, paramType, parameter);
}
handleResolvedValue(arg, namedValueInfo.name, parameter, mavContainer, webRequest);
return arg;
} else {
String name = ModelFactory.getNameForParameter(parameter);
Object attribute = (mavContainer.containsAttribute(name) ?
mavContainer.getModel().get(name) : createAttribute(name, parameter, binderFactory, webRequest));
WebDataBinder binder = binderFactory.createBinder(webRequest, attribute, name);
if (binder.getTarget() != null) {
bindRequestParameters(binder, webRequest);
validateIfApplicable(binder, parameter);
if (binder.getBindingResult().hasErrors() && isBindExceptionRequired(binder, parameter)) {
throw new BindException(binder.getBindingResult());
}
}
// Add resolved attribute and BindingResult at the end of the model
Map<String, Object> bindingResultModel = binder.getBindingResult().getModel();
mavContainer.removeAttributes(bindingResultModel);
mavContainer.addAllAttributes(bindingResultModel);
return binder.convertIfNecessary(binder.getTarget(), parameter.getParameterType(), parameter);
}
}
}
public Object resolveMapArgument(MethodParameter parameter, ModelAndViewContainer mavContainer,
NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {
Class<?> paramType = parameter.getParameterType();
Map<String, String[]> parameterMap = webRequest.getParameterMap();
if (MultiValueMap.class.isAssignableFrom(paramType)) {
MultiValueMap<String, String> result = new LinkedMultiValueMap<String, String>(parameterMap.size());
for (Map.Entry<String, String[]> entry : parameterMap.entrySet()) {
for (String value : entry.getValue()) {
result.add(entry.getKey(), value);
}
}
return result;
}
else {
Map<String, String> result = new LinkedHashMap<String, String>(parameterMap.size());
for (Map.Entry<String, String[]> entry : parameterMap.entrySet()) {
if (entry.getValue().length > 0) {
result.put(entry.getKey(), entry.getValue()[0]);
}
}
return result;
}
}
/**
* Obtain the named value for the given method parameter.
*/
private NamedValueInfo getNamedValueInfo(MethodParameter parameter) {
NamedValueInfo namedValueInfo = this.namedValueInfoCache.get(parameter);
if (namedValueInfo == null) {
namedValueInfo = createNamedValueInfo(parameter);
namedValueInfo = updateNamedValueInfo(parameter, namedValueInfo);
this.namedValueInfoCache.put(parameter, namedValueInfo);
}
return namedValueInfo;
}
protected NamedValueInfo createNamedValueInfo(MethodParameter parameter) {
RequestCustomParam ann = parameter.getParameterAnnotation(RequestCustomParam.class);
return (ann != null ? new RequestCustomParamNamedValueInfo(ann) : new RequestCustomParamNamedValueInfo());
}
protected Object resolveName(String name, MethodParameter parameter, NativeWebRequest webRequest) throws Exception {
HttpServletRequest servletRequest = webRequest.getNativeRequest(HttpServletRequest.class);
MultipartHttpServletRequest multipartRequest =
WebUtils.getNativeRequest(servletRequest, MultipartHttpServletRequest.class);
Object arg;
if (MultipartFile.class.equals(parameter.getParameterType())) {
assertIsMultipartRequest(servletRequest);
Assert.notNull(multipartRequest, "Expected MultipartHttpServletRequest: is a MultipartResolver configured?");
arg = multipartRequest.getFile(name);
}
else if (isMultipartFileCollection(parameter)) {
assertIsMultipartRequest(servletRequest);
Assert.notNull(multipartRequest, "Expected MultipartHttpServletRequest: is a MultipartResolver configured?");
arg = multipartRequest.getFiles(name);
}
else if (isMultipartFileArray(parameter)) {
assertIsMultipartRequest(servletRequest);
Assert.notNull(multipartRequest, "Expected MultipartHttpServletRequest: is a MultipartResolver configured?");
List<MultipartFile> multipartFiles = multipartRequest.getFiles(name);
arg = multipartFiles.toArray(new MultipartFile[multipartFiles.size()]);
}
else if ("javax.servlet.http.Part".equals(parameter.getParameterType().getName())) {
assertIsMultipartRequest(servletRequest);
arg = servletRequest.getPart(name);
}
else if (isPartCollection(parameter)) {
assertIsMultipartRequest(servletRequest);
arg = new ArrayList<Object>(servletRequest.getParts());
}
else if (isPartArray(parameter)) {
assertIsMultipartRequest(servletRequest);
arg = RequestPartResolver.resolvePart(servletRequest);
}
else {
arg = null;
if (multipartRequest != null) {
List<MultipartFile> files = multipartRequest.getFiles(name);
if (!files.isEmpty()) {
arg = (files.size() == 1 ? files.get(0) : files);
}
}
if (arg == null) {
String[] paramValues = webRequest.getParameterValues(name);
if (paramValues != null) {
arg = paramValues.length == 1 ? paramValues[0] : paramValues;
}
}
}
return arg;
}
private void assertIsMultipartRequest(HttpServletRequest request) {
String contentType = request.getContentType();
if (contentType == null || !contentType.toLowerCase().startsWith("multipart/")) {
throw new MultipartException("The current request is not a multipart request");
}
}
private boolean isMultipartFileCollection(MethodParameter parameter) {
Class<?> collectionType = getCollectionParameterType(parameter);
return ((collectionType != null) && collectionType.equals(MultipartFile.class));
}
private boolean isPartCollection(MethodParameter parameter) {
Class<?> collectionType = getCollectionParameterType(parameter);
return ((collectionType != null) && "javax.servlet.http.Part".equals(collectionType.getName()));
}
private boolean isPartArray(MethodParameter parameter) {
Class<?> paramType = parameter.getParameterType().getComponentType();
return ((paramType != null) && "javax.servlet.http.Part".equals(paramType.getName()));
}
private boolean isMultipartFileArray(MethodParameter parameter) {
Class<?> paramType = parameter.getParameterType().getComponentType();
return ((paramType != null) && MultipartFile.class.equals(paramType));
}
private Class<?> getCollectionParameterType(MethodParameter parameter) {
Class<?> paramType = parameter.getParameterType();
if (Collection.class.equals(paramType) || List.class.isAssignableFrom(paramType)){
Class<?> valueType = GenericCollectionTypeResolver.getCollectionParameterType(parameter);
if (valueType != null) {
return valueType;
}
}
return null;
}
protected void handleMissingValue(String name, MethodParameter parameter) throws ServletException {
throw new MissingServletRequestParameterException(name, parameter.getParameterType().getSimpleName());
}
public void contributeMethodArgument(MethodParameter parameter, Object value,
UriComponentsBuilder builder, Map<String, Object> uriVariables, ConversionService conversionService) {
Class<?> paramType = parameter.getParameterType();
if (Map.class.isAssignableFrom(paramType) || MultipartFile.class.equals(paramType) ||
"javax.servlet.http.Part".equals(paramType.getName())) {
return;
}
RequestCustomParam ann = parameter.getParameterAnnotation(RequestCustomParam.class);
String name = (ann == null || !StringUtils.hasText(ann.value()) ? parameter.getParameterName() : ann.value());
if (value == null) {
builder.queryParam(name);
}
else if (value instanceof Collection) {
for (Object element : (Collection<?>) value) {
element = formatUriValue(conversionService, TypeDescriptor.nested(parameter, 1), element);
builder.queryParam(name, element);
}
}
else {
builder.queryParam(name, formatUriValue(conversionService, new TypeDescriptor(parameter), value));
}
}
protected String formatUriValue(ConversionService cs, TypeDescriptor sourceType, Object value) {
if (value == null) {
return null;
}
else if (value instanceof String) {
return (String) value;
}
else if (cs != null) {
return (String) cs.convert(value, sourceType, STRING_TYPE_DESCRIPTOR);
}
else {
return value.toString();
}
}
/**
* Create a new NamedValueInfo based on the given NamedValueInfo with sanitized values.
*/
private NamedValueInfo updateNamedValueInfo(MethodParameter parameter, NamedValueInfo info) {
String name = info.name;
if (info.name.length() == 0) {
name = parameter.getParameterName();
if (name == null) {
throw new IllegalArgumentException("Name for argument type [" + parameter.getParameterType().getName() +
"] not available, and parameter name information not found in class file either.");
}
}
String defaultValue = (ValueConstants.DEFAULT_NONE.equals(info.defaultValue) ? null : info.defaultValue);
return new NamedValueInfo(name, info.required, defaultValue);
}
/**
* Resolves the given default value into an argument value.
*/
private Object resolveDefaultValue(String defaultValue) {
if (this.configurableBeanFactory == null) {
return defaultValue;
}
String placeholdersResolved = this.configurableBeanFactory.resolveEmbeddedValue(defaultValue);
BeanExpressionResolver exprResolver = this.configurableBeanFactory.getBeanExpressionResolver();
if (exprResolver == null) {
return defaultValue;
}
return exprResolver.evaluate(placeholdersResolved, this.expressionContext);
}
/**
* A {@code null} results in a {@code false} value for {@code boolean}s or an exception for other primitives.
*/
private Object handleNullValue(String name, Object value, Class<?> paramType) {
if (value == null) {
if (Boolean.TYPE.equals(paramType)) {
return Boolean.FALSE;
}
else if (paramType.isPrimitive()) {
throw new IllegalStateException("Optional " + paramType + " parameter '" + name +
"' is present but cannot be translated into a null value due to being declared as a " +
"primitive type. Consider declaring it as object wrapper for the corresponding primitive type.");
}
}
return value;
}
/**
* Invoked after a value is resolved.
* @param arg the resolved argument value
* @param name the argument name
* @param parameter the argument parameter type
* @param mavContainer the {@link ModelAndViewContainer}, which may be {@code null}
* @param webRequest the current request
*/
protected void handleResolvedValue(Object arg, String name, MethodParameter parameter,
ModelAndViewContainer mavContainer, NativeWebRequest webRequest) {
}
/**
* Extension point to create the model attribute if not found in the model.
* The default implementation uses the default constructor.
*
* @param attributeName the name of the attribute (never {@code null})
* @param methodParam the method parameter
* @param binderFactory for creating WebDataBinder instance
* @param request the current request
* @return the created model attribute (never {@code null})
*/
protected Object createAttribute(String attributeName, MethodParameter methodParam,
WebDataBinderFactory binderFactory, NativeWebRequest request) throws Exception {
return BeanUtils.instantiateClass(methodParam.getParameterType());
}
/**
* Extension point to bind the request to the target object.
*
* @param binder the data binder instance to use for the binding
* @param request the current request
*/
protected void bindRequestParameters(WebDataBinder binder, NativeWebRequest request) {
HttpServletRequest servletRequest = request.getNativeRequest(HttpServletRequest.class);
((ExtendedServletRequestDataBinder) binder).bind(servletRequest);
}
/**
* Validate the model attribute if applicable.
* <p>The default implementation checks for {@code @javax.validation.Valid},
* Spring's {@link org.springframework.validation.annotation.Validated},
* and custom annotations whose name starts with "Valid".
*
* @param binder the DataBinder to be used
* @param methodParam the method parameter
*/
protected void validateIfApplicable(WebDataBinder binder, MethodParameter methodParam) {
Annotation[] annotations = methodParam.getParameterAnnotations();
for (Annotation ann : annotations) {
Validated validatedAnn = AnnotationUtils.getAnnotation(ann, Validated.class);
if (validatedAnn != null || ann.annotationType().getSimpleName().startsWith("Valid")) {
Object hints = (validatedAnn != null ? validatedAnn.value() : AnnotationUtils.getValue(ann));
Object[] validationHints = (hints instanceof Object[] ? (Object[]) hints : new Object[]{hints});
binder.validate(validationHints);
break;
}
}
}
/**
* Whether to raise a fatal bind exception on validation errors.
*
* @param binder the data binder used to perform data binding
* @param methodParam the method argument
* @return {@code true} if the next method argument is not of type {@link Errors}
*/
protected boolean isBindExceptionRequired(WebDataBinder binder, MethodParameter methodParam) {
int i = methodParam.getParameterIndex();
Class<?>[] paramTypes = methodParam.getMethod().getParameterTypes();
boolean hasBindingResult = (paramTypes.length > (i + 1) && Errors.class.isAssignableFrom(paramTypes[i + 1]));
return !hasBindingResult;
}
public boolean supportsReturnType(MethodParameter returnType) {
if (returnType.getMethodAnnotation(RequestCustomParam.class) != null) {
return true;
} else
return this.annotationNotRequired && !BeanUtils.isSimpleProperty(returnType.getParameterType());
}
public void handleReturnValue(Object returnValue, MethodParameter returnType,
ModelAndViewContainer mavContainer, NativeWebRequest webRequest) throws Exception {
if (returnValue != null) {
String name = ModelFactory.getNameForReturnValue(returnValue, returnType);
mavContainer.addAttribute(name, returnValue);
}
}
private Object bindRequestParameters( MethodParameter parameter, HttpServletRequest servletRequest) throws Exception {
RequestCustomParam ann = parameter.getParameterAnnotation(RequestCustomParam.class);
String name = (ann == null || !StringUtils.hasText(ann.value()) ? parameter.getParameterName() : ann.value());
Object resultObj = null;
// 把reqeust的body读取到StringBuilder
BufferedReader reader = servletRequest.getReader();
StringBuilder sb = new StringBuilder();
char[] buf = new char[1024];
int rd;
while ((rd = reader.read(buf)) != -1) {
sb.append(buf, 0, rd);
}
String requestBody = sb.toString();
requestBody = requestBody.replaceAll("\r|\n|\r\n", "");
if (StringUtils.hasText(requestBody)) {
requestBodyCache = requestBody;
} else {
requestBody = requestBodyCache;
}
Class<?> parameterType = parameter.getParameterType();
String parameterTypeName = parameterType.getName();
if (BeanUtils.isSimpleProperty(parameterType)) {
try {
JSONObject json = JSONObject.parseObject(requestBody);
resultObj = json.get(name);
if (resultObj == null) {
Annotation annotaion = parameter.getParameterAnnotations()[0];
RequestCustomParam param = (RequestCustomParam) annotaion;
String defaultvalue = param.defaultValue();
defaultvalue = defaultvalue.replaceAll("\r|\n|\\s*", "");
resultObj= ConvertUtils.convert(defaultvalue, parameterType);
}
} catch (Exception e) {
throw new UnauthenticatedException(ErrorCode.INVALID_FIELD_ERROR, SpringUtils.getMessage(servletRequest, SpringUtils.INVALID_FIELD_ERROR_CODE));
}
} else if (BatchDto.class.isAssignableFrom(parameterType)) {
try {
resultObj = JSONObject.parseObject(requestBody, parameterType);
} catch (Exception e) {
throw new UnauthenticatedException(ErrorCode.INVALID_FIELD_ERROR, SpringUtils.getMessage(servletRequest, SpringUtils.INVALID_FIELD_ERROR_CODE));
}
} else {
try {
resultObj = JSONObject.parseObject(requestBody, parameterType);
} catch (Exception e) {
throw new UnauthenticatedException(ErrorCode.INVALID_FIELD_ERROR, SpringUtils.getMessage(servletRequest, SpringUtils.INVALID_FIELD_ERROR_CODE));
}
}
return resultObj;
}
private static class RequestCustomParamNamedValueInfo extends NamedValueInfo {
public RequestCustomParamNamedValueInfo() {
super("", false, ValueConstants.DEFAULT_NONE);
}
public RequestCustomParamNamedValueInfo(RequestCustomParam annotation) {
super(annotation.value(), annotation.required(), annotation.defaultValue());
}
}
private static class RequestPartResolver {
public static Object resolvePart(HttpServletRequest servletRequest) throws Exception {
return servletRequest.getParts().toArray(new Part[servletRequest.getParts().size()]);
}
}
/**
* Represents the information about a named value, including name, whether it's required and a default value.
*/
protected static class NamedValueInfo {
private final String name;
private final boolean required;
private final String defaultValue;
public NamedValueInfo(String name, boolean required, String defaultValue) {
this.name = name;
this.required = required;
this.defaultValue = defaultValue;
}
}
}
Step3:spring-mvc 配置文件添加自定义的参数解析器###
<mvc:annotation-driven>
<mvc:argument-resolvers>
<bean class="CustomMethodArgumentResolver" />
</mvc:argument-resolvers>
</mvc:annotation-driven>
Step4:使用范例###
public MessageResponse add(@RequestCustomParam User object,@RequestCustomParam(defaultValue = "" ) String companyId, HttpServletRequest request) {
}
源码地址：http://git.oschina.net/ly1022/Spring-mvc-Extends
参考资料：找不到原网址了，就是一个叫开涛的人写的博客，博客地址：http://jinnianshilongnian.iteye.com/