BAEL-3896: OpenAPI JSON Objects in Query Params

spring-rest-http/README.md

@@ -13,3 +13,4 @@ The "REST With Spring" Classes: http://bit.ly/restwithspring
 - [Spring RequestMapping](https://www.baeldung.com/spring-requestmapping)
 - [Guide to DeferredResult in Spring](https://www.baeldung.com/spring-deferred-result)
 - [Using JSON Patch in Spring REST APIs](https://www.baeldung.com/spring-rest-json-patch)
+- [OpenAPI JSON Objects in Query Params](https://www.baeldung.com/openapi-json-objects-in-query-params)

spring-rest-http/src/main/java/com/baeldung/jsonparam/JsonParamController.java

@@ -0,0 +1,55 @@
+package com.baeldung.jsonparam;
+
+import com.fasterxml.jackson.core.JsonParseException;
+import com.fasterxml.jackson.databind.JsonMappingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.*;
+
+import java.io.IOException;
+
+@Controller
+@RestController
+@RequestMapping("/api")
+public class JsonParamController {
+
+    @GetMapping(value = "/something")
+    public String testQueryParamApi(@RequestParam("params") String params) {
+        // params={"type":"foo","color":"green"}
+        ParamObjectDTO paramObjectDTO;
+        ObjectMapper objectMapper = new ObjectMapper();
+        try {
+            paramObjectDTO = objectMapper.readValue(params, ParamObjectDTO.class);
+            System.out.println(paramObjectDTO);
+            // use paramObjectDTO where you have {"type":"foo","color":"green"} JSON data as Object
+        } catch (JsonParseException e) {
+            e.printStackTrace();
+        } catch (JsonMappingException e) {
+            e.printStackTrace();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        return params;
+    }
+
+
+    @PostMapping(value = "/something")
+    public String testBodyParamApi(@RequestBody String params) {
+        // params={"type":"foo","color":"green"}
+        ParamObjectDTO paramObjectDTO;
+        ObjectMapper objectMapper = new ObjectMapper();
+        try {
+            paramObjectDTO = objectMapper.readValue(params, ParamObjectDTO.class);
+            System.out.println(paramObjectDTO);
+            // use paramObjectDTO where you have {"type":"foo","color":"green"} JSON data as Object
+        } catch (JsonParseException e) {
+            e.printStackTrace();
+        } catch (JsonMappingException e) {
+            e.printStackTrace();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        return params;
+    }
+
+}

spring-rest-http/src/main/java/com/baeldung/jsonparam/ParamObjectDTO.java

@@ -0,0 +1,33 @@
+package com.baeldung.jsonparam;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+
+@JsonIgnoreProperties(ignoreUnknown = true)
+public class ParamObjectDTO {
+    private String type;
+    private String color;
+
+    public String getType() {
+        return type;
+    }
+
+    public void setType(String type) {
+        this.type = type;
+    }
+
+    public String getColor() {
+        return color;
+    }
+
+    public void setColor(String color) {
+        this.color = color;
+    }
+
+    @Override
+    public String toString() {
+        return "ParamObjectDTO{" +
+                "type='" + type + '\'' +
+                ", color='" + color + '\'' +
+                '}';
+    }
+}