Toml#to(Class) converts to custom class

README.md

@@ -55,6 +55,41 @@ Long b = toml.getLong("b"); // returns 3
 Long c = toml.getLong("c"); // returns null
 ````
 
+### Custom classes
+
+A Toml object can be mapped to a custom class with the `Toml#to(Class<T>)` method.
+
+Any keys not found in both the TOML and the class are ignored.
+
+Key groups can be mapped to other custom classes or to `Map<String, Object>`.
+
+````
+name = "Mwanji Ezana"
+
+[address]
+  street = "123 A Street"
+  city = "AnyVille"
+````
+
+````java
+  public class Address {
+    private String street;
+    private String city;
+  }
+
+  public class User {
+    private String name;
+    private Address address;
+  }
+````
+
+````java
+Toml toml = new Toml().parse(tomlFile);
+User user = toml.to(User.class);
+````
+
+When defaults are present, a shallow merge is performed.
+
 ## TODO
 
 * Support all special characters

pom.xml

@@ -36,6 +36,11 @@
       <artifactId>parboiled-java</artifactId>
       <version>1.1.4</version>
     </dependency>
+    <dependency>
+      <groupId>com.google.code.gson</groupId>
+      <artifactId>gson</artifactId>
+      <version>2.2.2</version>
+    </dependency>
   </dependencies>
   <build>
     <plugins>

src/main/java/com/moandjiezana/toml/Toml.java

@@ -1,5 +1,7 @@
 package com.moandjiezana.toml;
 
+import com.google.gson.Gson;
+
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.util.Date;
@@ -116,4 +118,18 @@ public class Toml {
     this.values = values;
     this.defaults = null;
   }
+
+  public <T> T to(Class<T> targetClass) {
+    HashMap<String, Object> valuesCopy = new HashMap<String, Object>(values);
+    if (defaults != null) {
+      for (Map.Entry<String, Object> entry : defaults.values.entrySet()) {
+        if (!valuesCopy.containsKey(entry.getKey())) {
+          valuesCopy.put(entry.getKey(), entry.getValue());
+        }
+      }
+    }
+    Gson gson = new Gson();
+    String json = gson.toJson(valuesCopy);
+    return gson.fromJson(json, targetClass);
+  }
 }

src/test/java/com/moandjiezana/toml/TomlToClassTest.java

@@ -0,0 +1,75 @@
+package com.moandjiezana.toml;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import com.moandjiezana.toml.testutils.KeyGroupAsMap;
+import com.moandjiezana.toml.testutils.TomlKeyGroups;
+import com.moandjiezana.toml.testutils.TomlPrimitives;
+
+import java.io.File;
+import java.util.Calendar;
+import java.util.TimeZone;
+
+import org.junit.Test;
+
+public class TomlToClassTest {
+
+  @Test
+  public void should_convert_primitive_values() throws Exception {
+    Toml toml = new Toml().parse(file("should_convert_primitive_values.toml"));
+
+    TomlPrimitives values = toml.to(TomlPrimitives.class);
+
+    Calendar calendar = Calendar.getInstance();
+    calendar.set(1979, Calendar.MAY, 27, 7, 32, 00);
+    calendar.set(Calendar.MILLISECOND, 0);
+    calendar.setTimeZone(TimeZone.getTimeZone("UTC"));
+
+    assertEquals("string", values.string);
+    assertEquals((Long) 123L, values.number);
+    assertEquals(2.1, values.decimal, 0);
+    assertTrue(values.bool);
+    assertEquals(calendar.getTime(), values.date);
+  }
+
+  @Test
+  public void should_convert_key_groups() throws Exception {
+    String fileName = "should_convert_key_groups.toml";
+    Toml toml = new Toml().parse(file(fileName));
+
+    TomlKeyGroups tomlKeyGroups = toml.to(TomlKeyGroups.class);
+
+    assertEquals("value1", tomlKeyGroups.group1.string);
+    assertEquals("value2", tomlKeyGroups.group2.string);
+  }
+
+  @Test
+  public void should_use_defaults() throws Exception {
+    Toml defaults = new Toml().parse(file("should_convert_key_groups.toml"));
+    Toml toml = new Toml(defaults).parse("");
+
+    TomlKeyGroups tomlKeyGroups = toml.to(TomlKeyGroups.class);
+
+    assertEquals("value1", tomlKeyGroups.group1.string);
+    assertEquals("value2", tomlKeyGroups.group2.string);
+  }
+
+  @Test
+  public void should_ignore_keys_not_in_class() throws Exception {
+    TomlPrimitives tomlPrimitives = new Toml().parse("a=1\nstring=\"s\"").to(TomlPrimitives.class);
+
+    assertEquals("s", tomlPrimitives.string);
+  }
+
+  @Test
+  public void should_convert_key_group_as_map() throws Exception {
+    KeyGroupAsMap keyGroupAsMap = new Toml().parse("[group]\nkey=\"value\"").to(KeyGroupAsMap.class);
+
+    assertEquals("value", keyGroupAsMap.group.get("key"));
+  }
+
+  private File file(String fileName) {
+    return new File(getClass().getResource(fileName).getFile());
+  }
+}

src/test/java/com/moandjiezana/toml/testutils/KeyGroupAsMap.java

@@ -0,0 +1,8 @@
+package com.moandjiezana.toml.testutils;
+
+import java.util.Map;
+
+public class KeyGroupAsMap {
+
+  public Map<String, Object> group;
+}

src/test/java/com/moandjiezana/toml/testutils/TomlKeyGroups.java

@@ -0,0 +1,8 @@
+package com.moandjiezana.toml.testutils;
+
+
+public class TomlKeyGroups {
+
+  public TomlPrimitives group1;
+  public TomlPrimitives group2;
+}

src/test/java/com/moandjiezana/toml/testutils/TomlPrimitives.java

@@ -0,0 +1,13 @@
+package com.moandjiezana.toml.testutils;
+
+import java.util.Date;
+
+public class TomlPrimitives {
+
+  public String string;
+  public Long number;
+  public Double decimal;
+  public Boolean bool;
+  public Date date;
+
+}

src/test/resources/com/moandjiezana/toml/should_convert_key_groups.toml

@@ -0,0 +1,5 @@
+[group1]
+	string = "value1"
+
+[group2]
+	string = "value2"

src/test/resources/com/moandjiezana/toml/should_convert_primitive_values.toml

@@ -0,0 +1,5 @@
+string = "string"
+number = 123
+decimal = 2.1
+bool = true
+date = 1979-05-27T07:32:00Z