Merge pull request #14094 from thibaultfaure/article/BAEL-6508

BAEL-6508 Code for the Solving Gson Parsing Errors article

json-modules/gson-2/README.md

@@ -0,0 +1,7 @@
+## GSON
+
+This module contains articles about Gson
+
+### Relevant Articles: 
+
+

json-modules/gson-2/pom.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xmlns="http://maven.apache.org/POM/4.0.0"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>gson-2</artifactId>
+    <name>gson-2</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>json-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.google.code.gson</groupId>
+            <artifactId>gson</artifactId>
+            <version>${gson.version}</version>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <gson.version>2.10.1</gson.version>
+    </properties>
+
+</project>

json-modules/gson-2/src/main/java/com/baeldung/gson/parsingerrors/Person.java

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+package com.baeldung.gson.parsingerrors;
+
+public class Person {
+
+    public String name;
+
+    public String getName() {
+        return name;
+    }
+
+    public Person(String name) {
+        this.name = name;
+    }
+
+}

json-modules/gson-2/src/test/java/com/baeldung/gson/parsingerror/GsonErrorDemoUnitTest.java

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+package com.baeldung.gson.parsingerror;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import java.lang.reflect.Type;
+import java.util.Collection;
+
+import org.junit.jupiter.api.Test;
+
+import com.baeldung.gson.parsingerrors.Person;
+import com.google.gson.Gson;
+import com.google.gson.JsonSyntaxException;
+import com.google.gson.reflect.TypeToken;
+
+class GsonErrorDemoUnitTest {
+
+    @Test
+    void givenAJsonArray_WhenTellingGsonToExpectAnObject_ThenThrows() {
+        assertThrows(JsonSyntaxException.class, () -> {
+            Person person = new Gson().fromJson("[{\"name\":\"John\"},{\"name\":\"James\"}]", Person.class);
+        });
+    }
+
+    @Test
+    void givenAJsonArray_WhenParsingIntoAnArray_ThenOK() {
+        Person[] personArray = new Gson().fromJson("[{\"name\":\"John\"},{\"name\":\"James\"}]", Person[].class);
+        assertThat(personArray).extracting(Person::getName)
+          .containsExactly("John", "James");
+    }
+
+    @Test
+    void givenAJsonArray_WhenParsingIntoACollection_ThenOK() {
+        Type collectionType = new TypeToken<Collection<Person>>() {
+        }.getType();
+        Collection<Person> personCollection = new Gson().fromJson("[{\"name\":\"John\"},{\"name\":\"James\"}]", collectionType);
+        assertThat(personCollection).extracting(Person::getName)
+          .containsExactly("John", "James");
+    }
+
+    @Test
+    void givenAJsonObject_WhenTellingGsonToExpectAnArray_ThenThrows() {
+        assertThrows(JsonSyntaxException.class, () -> {
+            Person[] personArray = new Gson().fromJson("{\"name\":\"John\"}", Person[].class);
+        });
+    }
+
+    @Test
+    void givenAJsonObject_WhenParsingIntoAnObject_ThenOK() {
+        Person person = new Gson().fromJson("{\"name\":\"John\"}", Person.class);
+        assertEquals("John", person.getName());
+    }
+
+}

json-modules/pom.xml

@@ -18,6 +18,7 @@
         <module>json-2</module>
         <module>json-path</module>
         <module>gson</module>
+        <module>gson-2</module>
     </modules>
 
     <build>