EN
Spring Boot 2 - request mapping with wildcard parameter (/path/**)
6 points
In this short article, we would like to show how to get wildcard request parameters (under stars parameter from /some/path/**) from URL in Spring Boot 2.
Quick solution:
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package example.controllers;2
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import org.springframework.beans.factory.annotation.Autowired;4
import org.springframework.http.ResponseEntity;5
import org.springframework.stereotype.Controller;6
import org.springframework.util.PathMatcher;7
import org.springframework.web.bind.annotation.PathVariable;8
import org.springframework.web.bind.annotation.RequestMapping;9
import org.springframework.web.bind.annotation.RequestMethod;10
import org.springframework.web.servlet.HandlerMapping;11
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import javax.servlet.http.HttpServletRequest;13
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public class ExampleController {16
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private PathMatcher pathMatcher;19
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private String getWildcardParam(HttpServletRequest request) {21
String patternAttribute = (String) request.getAttribute(HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE);22
String mappingAttribute = (String) request.getAttribute(HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE);23
return this.pathMatcher.extractPathWithinPattern(patternAttribute, mappingAttribute);24
}25
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(27
method = RequestMethod.GET,28
value = "/items/{itemId}/**"29
)30
public ResponseEntity<String> getItem(HttpServletRequest request, String itemId) {31
String wildcardParam = this.getWildcardParam(request); // <--- extracts all data located under **32
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// Some logic here ...34
}35
}
This section contains an example source code, how to create and use simple @WildcardParam annotation.
Simple steps:
- create wildcard annotation to simplify controller mappings usage,
- register wildcard annotation in application configuration,
- use wildcard parameters in
@PathVariableway.
ExampleController.java file:
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package example.controllers;2
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import example.annotations.WildcardParam;4
import org.springframework.beans.factory.annotation.Autowired;5
import org.springframework.http.HttpStatus;6
import org.springframework.http.ResponseEntity;7
import org.springframework.stereotype.Controller;8
import org.springframework.web.bind.annotation.*;9
import org.springframework.web.servlet.HandlerMapping;10
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import javax.servlet.ServletException;12
import javax.servlet.http.HttpServletRequest;13
import javax.servlet.http.Part;14
import java.io.IOException;15
import java.net.URISyntaxException;16
import java.util.Collection;17
import java.util.function.Function;18
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public class ExampleController {21
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(23
method = RequestMethod.GET,24
value = "/items/{itemId}/**"25
)26
public ResponseEntity<String> getItem(27
String itemId,28
String itemResource // <--- contains all data located under **29
) {30
// Some logic here ...31
}32
}WildcardParam.java file:
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package example.annotations;2
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import org.springframework.core.MethodParameter;4
import org.springframework.util.PathMatcher;5
import org.springframework.web.bind.support.WebDataBinderFactory;6
import org.springframework.web.context.request.NativeWebRequest;7
import org.springframework.web.method.support.HandlerMethodArgumentResolver;8
import org.springframework.web.method.support.ModelAndViewContainer;9
import org.springframework.web.servlet.HandlerMapping;10
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import javax.servlet.http.HttpServletRequest;12
import java.lang.annotation.*;13
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(ElementType.PARAMETER)15
(RetentionPolicy.RUNTIME)16
public @interface WildcardParam {17
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class Resolver implements HandlerMethodArgumentResolver {19
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private PathMatcher pathMatcher;21
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public Resolver(PathMatcher pathMatcher) {23
this.pathMatcher = pathMatcher;24
}25
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public boolean supportsParameter(MethodParameter methodParameter) {28
Annotation annotation = methodParameter.getParameterAnnotation(WildcardParam.class);29
return annotation != null;30
}31
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public Object resolveArgument(MethodParameter methodParameter, ModelAndViewContainer modeContainer, NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {34
HttpServletRequest servletRequest = webRequest.getNativeRequest(HttpServletRequest.class);35
if (servletRequest == null) {36
return null;37
}38
String patternAttribute = (String) servletRequest.getAttribute(HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE);39
String mappingAttribute = (String) servletRequest.getAttribute(HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE);40
return this.pathMatcher.extractPathWithinPattern(patternAttribute, mappingAttribute);41
}42
}43
}MVCConfig.java file:
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package example.config;2
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import example.annotations.WildcardParam;4
import org.springframework.beans.factory.annotation.Autowired;5
import org.springframework.context.annotation.Configuration;6
import org.springframework.util.PathMatcher;7
import org.springframework.web.method.support.HandlerMethodArgumentResolver;8
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;9
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import java.util.List;11
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public class MVCConfig implements WebMvcConfigurer {14
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private PathMatcher pathMatcher; // or replace it with bean creation function17
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public void addArgumentResolvers(List<HandlerMethodArgumentResolver> resolvers) {20
resolvers.add(new WildcardParam.Resolver(this.pathMatcher));21
}22
}