Merge pull request #10429 from azhwani/BAEL-4739

BAEL-4739: Spring RestTemplate Exception

spring-web-modules/spring-resttemplate-2/src/main/java/com/baeldung/resttemplateexception/RestTemplateExceptionApplication.java

@@ -0,0 +1,13 @@
+package com.baeldung.resttemplateexception;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class RestTemplateExceptionApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(RestTemplateExceptionApplication.class, args);
+    }
+
+}

spring-web-modules/spring-resttemplate-2/src/main/java/com/baeldung/resttemplateexception/controller/ProductApi.java

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+package com.baeldung.resttemplateexception.controller;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.baeldung.resttemplateexception.model.Criterion;
+import com.baeldung.resttemplateexception.model.Product;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonMappingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+@RestController
+@RequestMapping("/api")
+public class ProductApi {
+
+    private List<Product> productList = new ArrayList<>(Arrays.asList(new Product(1, "Acer Aspire 5", 437), new Product(2, "ASUS VivoBook", 650), new Product(3, "Lenovo Legion", 990)));
+
+    @GetMapping("/get")
+    public Product get(@RequestParam String criterion) throws JsonMappingException, JsonProcessingException {
+        ObjectMapper objectMapper = new ObjectMapper();
+        Criterion crt = objectMapper.readValue(criterion, Criterion.class);
+        if (crt.getProp().equals("name"))
+            return findByName(crt.getValue());
+
+        // Search by other properties (id,price)
+
+        return null;
+    }
+
+    private Product findByName(String name) {
+        for (Product product : this.productList) {
+            if (product.getName().equals(name)) {
+                return product;
+            }
+        }
+        return null;
+    }
+
+    // Other methods
+}

spring-web-modules/spring-resttemplate-2/src/main/java/com/baeldung/resttemplateexception/model/Criterion.java

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+package com.baeldung.resttemplateexception.model;
+
+public class Criterion {
+
+    private String prop;
+    private String value;
+
+    public Criterion() {
+
+    }
+
+    public String getProp() {
+        return prop;
+    }
+
+    public void setProp(String prop) {
+        this.prop = prop;
+    }
+
+    public String getValue() {
+        return value;
+    }
+
+    public void setValue(String value) {
+        this.value = value;
+    }
+
+}

spring-web-modules/spring-resttemplate-2/src/main/java/com/baeldung/resttemplateexception/model/Product.java

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

spring-web-modules/spring-resttemplate-2/src/test/java/com/baeldung/resttemplateexception/RestTemplateExceptionLiveTest.java

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+package com.baeldung.resttemplateexception;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.web.client.RestTemplate;
+import org.springframework.web.util.UriComponentsBuilder;
+
+import com.baeldung.resttemplateexception.model.Product;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(classes = { RestTemplate.class, RestTemplateExceptionApplication.class })
+public class RestTemplateExceptionLiveTest {
+
+    @Autowired
+    RestTemplate restTemplate;
+
+    @Test(expected = IllegalArgumentException.class)
+    public void givenGetUrl_whenJsonIsPassed_thenThrowException() {
+        String url = "http://localhost:8080/spring-rest/api/get?criterion={\"prop\":\"name\",\"value\":\"ASUS VivoBook\"}";
+        Product product = restTemplate.getForObject(url, Product.class);
+    }
+
+    @Test
+    public void givenGetUrl_whenJsonIsPassed_thenGetProduct() {
+        String criterion = "{\"prop\":\"name\",\"value\":\"ASUS VivoBook\"}";
+        String url = "http://localhost:8080/spring-rest/api/get?criterion={criterion}";
+        Product product = restTemplate.getForObject(url, Product.class, criterion);
+
+        assertEquals(product.getPrice(), 650, 0);
+    }
+
+    @Test
+    public void givenGetUrl_whenJsonIsPassed_thenReturnProduct() {
+        String criterion = "{\"prop\":\"name\",\"value\":\"Acer Aspire 5\"}";
+        String url = "http://localhost:8080/spring-rest/api/get";
+
+        UriComponentsBuilder builder = UriComponentsBuilder.fromUriString(url).queryParam("criterion", criterion);
+        Product product = restTemplate.getForObject(builder.build().toUri(), Product.class);
+
+        assertEquals(product.getId(), 1, 0);
+    }
+}