BAEL-4327: JSON Parameters with Spring MVC (#10036)

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* update commit

Co-authored-by: azhwani <>

spring-mvc-basics-4/src/main/java/com/baeldung/jsonparams/config/JsonParamsConfig.java

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+package com.baeldung.jsonparams.config;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.web.servlet.ViewResolver;
+import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
+import org.springframework.web.servlet.config.annotation.EnableWebMvc;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
+import org.springframework.web.servlet.view.InternalResourceViewResolver;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+@Configuration
+@EnableWebMvc
+@ComponentScan(basePackages = { "com.baeldung.jsonparams" })
+public class JsonParamsConfig implements WebMvcConfigurer {
+    @Override
+    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
+        configurer.enable();
+    }
+
+    @Bean
+    public ViewResolver viewResolver() {
+        InternalResourceViewResolver bean = new InternalResourceViewResolver();
+        bean.setPrefix("/WEB-INF/");
+        bean.setSuffix(".jsp");
+        return bean;
+    }
+
+    @Bean
+    public ObjectMapper objectMapper() {
+        return new ObjectMapper();
+    }
+
+}

spring-mvc-basics-4/src/main/java/com/baeldung/jsonparams/config/JsonParamsInit.java

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+package com.baeldung.jsonparams.config;
+
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRegistration;
+
+import org.springframework.web.context.ContextLoaderListener;
+import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
+import org.springframework.web.servlet.DispatcherServlet;
+
+public class JsonParamsInit // implements WebApplicationInitializer 
+{
+
+    //uncomment to run the product controller example
+    //@Override
+    public void onStartup(ServletContext sc) throws ServletException {
+        AnnotationConfigWebApplicationContext root = new AnnotationConfigWebApplicationContext();
+        root.register(JsonParamsConfig.class);
+        root.setServletContext(sc);
+        sc.addListener(new ContextLoaderListener(root));
+
+        DispatcherServlet dv = new DispatcherServlet(root);
+
+        ServletRegistration.Dynamic appServlet = sc.addServlet("jsonparams-mvc", dv);
+        appServlet.setLoadOnStartup(1);
+        appServlet.addMapping("/");
+    }
+
+}

spring-mvc-basics-4/src/main/java/com/baeldung/jsonparams/controller/ProductController.java

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+package com.baeldung.jsonparams.controller;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.WebDataBinder;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.InitBinder;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.ResponseBody;
+
+import com.baeldung.jsonparams.model.Product;
+import com.baeldung.jsonparams.propertyeditor.ProductEditor;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonMappingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+@Controller
+@RequestMapping("/products")
+public class ProductController {
+
+    private ObjectMapper objectMapper;
+
+    @Autowired
+    public void setObjectMapper(ObjectMapper objectMapper) {
+        this.objectMapper = objectMapper;
+    }
+
+    @InitBinder
+    public void initBinder(WebDataBinder binder) {
+        binder.registerCustomEditor(Product.class, new ProductEditor(objectMapper));
+    }
+
+    @PostMapping("/create")
+    @ResponseBody
+    public Product createProduct(@RequestBody Product product) {
+        // custom logic
+        return product;
+    }
+
+    @GetMapping("/get")
+    @ResponseBody
+    public Product getProduct(@RequestParam String product) throws JsonMappingException, JsonProcessingException {
+        final Product prod = objectMapper.readValue(product, Product.class);
+        return prod;
+    }
+
+    @GetMapping("/get2")
+    @ResponseBody
+    public Product get2Product(@RequestParam Product product) {
+        // custom logic
+        return product;
+    }
+
+}

spring-mvc-basics-4/src/main/java/com/baeldung/jsonparams/model/Product.java

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+package com.baeldung.jsonparams.model;
+
+public class Product {
+
+    private int id;
+    private String name;
+    private double price;
+
+    public Product() {
+
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public void setId(int id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String nom) {
+        this.name = nom;
+    }
+
+    public double getPrice() {
+        return price;
+    }
+
+    public void setPrice(double price) {
+        this.price = price;
+    }
+
+}

spring-mvc-basics-4/src/main/java/com/baeldung/jsonparams/propertyeditor/ProductEditor.java

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+package com.baeldung.jsonparams.propertyeditor;
+
+import java.beans.PropertyEditorSupport;
+
+import org.springframework.util.StringUtils;
+
+import com.baeldung.jsonparams.model.Product;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+public class ProductEditor extends PropertyEditorSupport {
+
+    private ObjectMapper objectMapper;
+
+    public ProductEditor(ObjectMapper objectMapper) {
+        this.objectMapper = objectMapper;
+    }
+
+    @Override
+    public void setAsText(String text) throws IllegalArgumentException {
+        if (StringUtils.isEmpty(text)) {
+            setValue(null);
+        } else {
+            Product prod = new Product();
+            try {
+                prod = objectMapper.readValue(text, Product.class);
+            } catch (JsonProcessingException e) {
+                throw new IllegalArgumentException(e);
+            }
+            setValue(prod);
+        }
+    }
+
+}

spring-mvc-basics-4/src/test/java/com/baeldung/jsonparams/JsonParamsIntegrationTest.java

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+package com.baeldung.jsonparams;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.MediaType;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.web.AnnotationConfigWebContextLoader;
+import org.springframework.test.context.web.WebAppConfiguration;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+import org.springframework.web.context.WebApplicationContext;
+
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.*;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.*;
+
+import com.baeldung.jsonparams.config.JsonParamsConfig;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@WebAppConfiguration
+@ContextConfiguration(classes = { JsonParamsConfig.class }, loader = AnnotationConfigWebContextLoader.class)
+public class JsonParamsIntegrationTest {
+
+    private MockMvc mockMvc;
+
+    @Autowired
+    private WebApplicationContext wac;
+
+    @Before
+    public void setUp() {
+        this.mockMvc = MockMvcBuilders.webAppContextSetup(this.wac)
+            .build();
+    }
+
+    @Test
+    public void whenJsonIsPassedWithPost_thenResponseOK() throws Exception {
+
+        this.mockMvc.perform(post("/products/create").accept(MediaType.APPLICATION_JSON)
+            .contentType(MediaType.APPLICATION_JSON)
+            .content("{\"id\": 1,\"name\": \"Asus Zenbook\",\"price\": 800}"))
+            .andExpect(status().isOk())
+            .andExpect(jsonPath("$.id").value("1"))
+            .andExpect(jsonPath("$.name").value("Asus Zenbook"));
+
+    }
+
+    @Test
+    public void whenJsonIsPassedWithGet_thenResponseOK() throws Exception {
+
+        this.mockMvc.perform(get("/products/get").contentType(MediaType.APPLICATION_JSON)
+            .queryParam("product", "{\"id\": 2,\"name\": \"HP EliteBook\",\"price\": 700}"))
+            .andExpect(status().isOk())
+            .andExpect(jsonPath("$.id").value("2"))
+            .andExpect(jsonPath("$.name").value("HP EliteBook"));
+
+    }
+
+    @Test
+    public void whenJsonIsPassedWithGet2_thenResponseOK() throws Exception {
+
+        this.mockMvc.perform(get("/products/get2").contentType(MediaType.APPLICATION_JSON)
+            .queryParam("product", "{\"id\": 3,\"name\": \"Dell G5 15\",\"price\": 1200}"))
+            .andExpect(status().isOk())
+            .andExpect(jsonPath("$.id").value("3"))
+            .andExpect(jsonPath("$.name").value("Dell G5 15"));
+
+    }
+
+}