Article: Converting Object To Map in Java (#14160)

This commit is related to the article entitled "Converting Object To Map in Java"

core-java-modules/core-java-collections-maps-6/src/test/com/baeldung/objecttomap/ObjectToMapUnitTest.java

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+package java.com.baeldung.objecttomap;
+import com.google.gson.Gson;
+import org.junit.Assert;
+import org.junit.Test;
+import wiremock.com.fasterxml.jackson.core.type.TypeReference;
+import wiremock.com.fasterxml.jackson.databind.ObjectMapper;
+import wiremock.com.google.common.reflect.TypeToken;
+import java.lang.reflect.Field;
+import java.util.HashMap;
+import java.util.Map;
+
+public class ObjectToMapUnitTest {
+    Employee employee = new Employee("John", 3000.0);
+
+    @Test
+    public void givenJavaObject_whenUsingReflection_thenConvertToMap() throws IllegalAccessException {
+        Map<String, Object> map = convertUsingReflection(employee);
+        Assert.assertEquals(employee.getName(), map.get("name"));
+        Assert.assertEquals(employee.getSalary(), map.get("salary"));
+    }
+
+    private Map<String, Object> convertUsingReflection(Object object) throws IllegalAccessException {
+        Map<String, Object> map = new HashMap<>();
+        Field[] fields = object.getClass().getDeclaredFields();
+
+        for (Field field : fields) {
+            field.setAccessible(true);
+            map.put(field.getName(), field.get(object));
+        }
+
+        return map;
+    }
+
+    @Test
+    public void givenJavaObject_whenUsingJackson_thenConvertToMap() {
+        ObjectMapper objectMapper = new ObjectMapper();
+        Map<String, Object> map = objectMapper.convertValue(employee, new TypeReference<Map<String, Object>>() {});
+        Assert.assertEquals(employee.getName(), map.get("name"));
+        Assert.assertEquals(employee.getSalary(), map.get("salary"));
+    }
+
+    @Test
+    public void givenJavaObject_whenUsingGson_thenConvertToMap() {
+        Gson gson = new Gson();
+        String json = gson.toJson(employee);
+        Map<String, Object> map = gson.fromJson(json, new TypeToken<Map<String, Object>>() {}.getType());
+        Assert.assertEquals(employee.getName(), map.get("name"));
+        Assert.assertEquals(employee.getSalary(), map.get("salary"));
+    }
+
+    private static class Employee {
+        private String name;
+        private Double salary;
+
+        public Employee(String name, Double salary) {
+            this.name = name;
+            this.salary = salary;
+        }
+
+        public String getName() {
+            return name;
+        }
+
+        public void setName(String name) {
+            this.name = name;
+        }
+
+        public Double getSalary() {
+            return salary;
+        }
+
+        public void setSalary(Double age) {
+            this.salary = salary;
+        }
+    }
+}