BAEL-6080: Getting Query String Parameters from HttpServletRequest

spring-web-modules/spring-mvc-basics-5/src/main/java/com/baeldung/requestparam/QueryStringController.java

@@ -0,0 +1,64 @@
+package com.baeldung.requestparam;
+
+import jakarta.servlet.http.HttpServletRequest;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+
+@RestController
+public class QueryStringController {
+
+    @GetMapping("/api/user0")
+    public String byGetQueryString(HttpServletRequest request) {
+        return request.getQueryString();
+    }
+
+    @GetMapping("/api/user1")
+    public String byGetParameter(HttpServletRequest request) {
+        String username = request.getParameter("username");
+        return "username:" + username;
+    }
+
+    @GetMapping("/api/user2")
+    public String byGetParameterValues(HttpServletRequest request) {
+        String[] roles = request.getParameterValues("roles");
+        return "roles:" + Arrays.toString(roles);
+    }
+
+    @GetMapping("/api/user3")
+    public UserDTO byGetParameterMap(HttpServletRequest request) {
+        Map<String, String[]> parameterMap = request.getParameterMap();
+        String[] usernames = parameterMap.get("username");
+        String[] roles = parameterMap.get("roles");
+        UserDTO userDTO = new UserDTO();
+        userDTO.setUsername(usernames[0]);
+        userDTO.setRoles(Arrays.asList(roles));
+        return userDTO;
+    }
+
+    @GetMapping("/api/user4")
+    public UserDTO byParameterName(String username, String[] roles) {
+        UserDTO userDTO = new UserDTO();
+        userDTO.setUsername(username);
+        userDTO.setRoles(Arrays.asList(roles));
+        return userDTO;
+    }
+
+    @GetMapping("/api/user5")
+    public UserDTO byRequestParamAnnotation(@RequestParam("username") String var1, @RequestParam("roles") List<String> var2) {
+        UserDTO userDTO = new UserDTO();
+        userDTO.setUsername(var1);
+        userDTO.setRoles(var2);
+        return userDTO;
+    }
+
+    @GetMapping("/api/user6")
+    public UserDTO byPojo(UserDTO userDTO) {
+        return userDTO;
+    }
+
+}

spring-web-modules/spring-mvc-basics-5/src/main/java/com/baeldung/requestparam/UserDTO.java

@@ -0,0 +1,24 @@
+package com.baeldung.requestparam;
+
+import java.util.List;
+
+public class UserDTO {
+    private String username;
+    private List<String> roles;
+
+    public String getUsername() {
+        return username;
+    }
+
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    public List<String> getRoles() {
+        return roles;
+    }
+
+    public void setRoles(List<String> roles) {
+        this.roles = roles;
+    }
+}

spring-web-modules/spring-mvc-basics-5/src/test/java/com/baeldung/requestparam/QueryStringControllerIntegrationTest.java

@@ -0,0 +1,64 @@
+package com.baeldung.requestparam;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.web.servlet.MockMvc;
+
+import static org.hamcrest.Matchers.containsInRelativeOrder;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;
+import static org.springframework.test.web.servlet.setup.MockMvcBuilders.standaloneSetup;
+
+
+@SpringBootTest
+@AutoConfigureMockMvc
+class QueryStringControllerIntegrationTest {
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @BeforeEach
+    public void setup() {
+        this.mockMvc = standaloneSetup(new QueryStringController()).build();
+    }
+
+    @Test
+    public void whenInvokeGetQueryString_thenReturnTheOriginQueryString() throws Exception {
+        this.mockMvc.perform(get("/api/user0?username=bob&roles=admin&roles=stuff"))
+                    .andExpect(status().isOk())
+                    .andExpect(content().string("username=bob&roles=admin&roles=stuff"));
+    }
+
+    @Test
+    public void whenInvokeGetQueryParameter_thenReturnOneParameterValue() throws Exception {
+        this.mockMvc.perform(get("/api/user1?username=bob"))
+                    .andExpect(status().isOk())
+                    .andExpect(content().string("username:bob"));
+    }
+
+    @Test
+    public void whenInvokeGetParameterValues_thenReturnParameterAsArray() throws Exception {
+        this.mockMvc.perform(get("/api/user2?roles=admin&roles=stuff"))
+                    .andExpect(status().isOk())
+                    .andExpect(content().string("roles:[admin, stuff]"));
+    }
+
+    @ParameterizedTest
+    @CsvSource(textBlock = """
+            /api/user3
+            /api/user4
+            /api/user5
+            /api/user6
+            """)
+    public void whenPassParameters_thenReturnResolvedModel(String path) throws Exception {
+        this.mockMvc.perform(get(path + "?username=bob&roles=admin&roles=stuff"))
+                    .andExpect(status().isOk())
+                    .andExpect(jsonPath("$.username").value("bob"))
+                    .andExpect(jsonPath("$.roles").value(containsInRelativeOrder("admin", "stuff")));
+    }
+}