see 04/06 log

build.gradle

@@ -40,6 +40,7 @@ ext {
     support_version = '27.0.2'
 
     leakcanary_version = '1.5.4'
+    gson_version = '2.8.2'
 
     junit_version = '4.12'
     robolectric_version = '3.1.2'

subutil/build.gradle

@@ -35,7 +35,9 @@ android {
 dependencies {
     compileOnly "com.android.support:appcompat-v7:$support_version"
     compileOnly "com.android.support:design:$support_version"
+    compileOnly "com.google.code.gson:gson:$gson_version"
 
+    testImplementation "com.google.code.gson:gson:$gson_version"
     testImplementation "junit:junit:$junit_version"
     testImplementation "org.robolectric:robolectric:$robolectric_version"
 }
\ No newline at end of file

subutil/src/main/java/com/blankj/subutil/util/GsonUtils.java

+package com.blankj.subutil.util;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+
+import java.io.Reader;
+import java.lang.reflect.Type;
+
+
+/**
+ * <pre>
+ *     author: Blankj
+ *     blog  : http://blankj.com
+ *     time  : 2018/04/05
+ *     desc  :
+ * </pre>
+ */
+public final class GsonUtils {
+
+    private static final Gson GSON = createGson(true);
+
+    private static final Gson GSON_NO_NULLS = createGson(false);
+
+    private GsonUtils() {
+        throw new UnsupportedOperationException("u can't instantiate me...");
+    }
+
+    /**
+     * Gets pre-configured {@link Gson} instance.
+     *
+     * @return {@link Gson} instance.
+     */
+    public static Gson getGson() {
+        return getGson(true);
+    }
+
+    /**
+     * Gets pre-configured {@link Gson} instance.
+     *
+     * @param serializeNulls determines if nulls will be serialized.
+     * @return {@link Gson} instance.
+     */
+    public static Gson getGson(final boolean serializeNulls) {
+        return serializeNulls ? GSON_NO_NULLS : GSON;
+    }
+
+    /**
+     * Serializes an object into json.
+     *
+     * @param object the object to serialize.
+     * @return object serialized into json.
+     */
+    public static String toJson(final Object object) {
+        return toJson(object, true);
+    }
+
+    /**
+     * Serializes an object into json.
+     *
+     * @param object       the object to serialize.
+     * @param includeNulls determines if nulls will be included.
+     * @return object serialized into json.
+     */
+    public static String toJson(final Object object, final boolean includeNulls) {
+        return includeNulls ? GSON.toJson(object) : GSON_NO_NULLS.toJson(object);
+    }
+
+
+    /**
+     * Converts {@link String} to given type.
+     *
+     * @param json the json to convert.
+     * @param type type type json will be converted to.
+     * @return instance of type
+     */
+    public static <T> T fromJson(final String json, final Class<T> type) {
+        return GSON.fromJson(json, type);
+    }
+
+    /**
+     * Converts {@link String} to given type.
+     *
+     * @param json the json to convert.
+     * @param type type type json will be converted to.
+     * @return instance of type
+     */
+    public static <T> T fromJson(final String json, final Type type) {
+        return GSON.fromJson(json, type);
+    }
+
+    /**
+     * Converts {@link Reader} to given type.
+     *
+     * @param reader the reader to convert.
+     * @param type   type type json will be converted to.
+     * @return instance of type
+     */
+    public static <T> T fromJson(final Reader reader, final Class<T> type) {
+        return GSON.fromJson(reader, type);
+    }
+
+    /**
+     * Converts {@link Reader} to given type.
+     *
+     * @param reader the reader to convert.
+     * @param type   type type json will be converted to.
+     * @return instance of type
+     */
+    public static <T> T fromJson(final Reader reader, final Type type) {
+        return GSON.fromJson(reader, type);
+    }
+
+    /**
+     * Create a pre-configured {@link Gson} instance.
+     *
+     * @param serializeNulls determines if nulls will be serialized.
+     * @return {@link Gson} instance.
+     */
+    private static Gson createGson(final boolean serializeNulls) {
+        final GsonBuilder builder = new GsonBuilder();
+        if (serializeNulls) builder.serializeNulls();
+        return builder.create();
+    }
+}

subutil/src/test/java/com/blankj/subutil/util/ClipboardUtilsTest.java

@@ -16,7 +16,7 @@ import static org.junit.Assert.assertEquals;
  *     author: Blankj
  *     blog  : http://blankj.com
  *     time  : 2016/09/26
- *     desc  : ClipboardUtils单元测试
+ *     desc  : ClipboardUtils 单元测试
  * </pre>
  */
 @RunWith(RobolectricTestRunner.class)

subutil/src/test/java/com/blankj/subutil/util/CoordinateConvertUtilsTest.java

@@ -10,7 +10,7 @@ import static java.lang.Math.PI;
  *     author: Blankj
  *     blog  : http://blankj.com
  *     time  : 2018/03/22
- *     desc  :
+ *     desc  : CoordinateConvertUtils 单元测试
  * </pre>
  */
 public class CoordinateConvertUtilsTest {

subutil/src/test/java/com/blankj/subutil/util/GsonUtilsTest.java

+package com.blankj.subutil.util;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+
+/**
+ * <pre>
+ *     author: Blankj
+ *     blog  : http://blankj.com
+ *     time  : 2016/09/26
+ *     desc  : GsonUtils 单元测试
+ * </pre>
+ */
+public class GsonUtilsTest {
+
+    @Test
+    public void getGson() {
+        Assert.assertNotNull(GsonUtils.getGson());
+        Assert.assertNotNull(GsonUtils.getGson(false));
+    }
+
+    @Test
+    public void toJson() {
+        Person person = new Person("Blankj");
+        System.out.println(GsonUtils.toJson(person));
+        System.out.println(GsonUtils.toJson(person, false));
+    }
+
+    @Test
+    public void fromJson() {
+        Person person = new Person("Blankj");
+        Assert.assertEquals(
+                person,
+                GsonUtils.fromJson("{\"name\":\"Blankj\",\"gender\":0,\"address\":null}", Person.class)
+        );
+        Assert.assertEquals(
+                person,
+                GsonUtils.fromJson("{\"name\":\"Blankj\",\"gender\":0}", Person.class)
+        );
+    }
+
+    class Person {
+
+        String name;
+        int    gender;
+        String address;
+
+        public Person(String name) {
+            this.name = name;
+            this.gender = gender;
+            this.address = address;
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (obj == this) return true;
+            if (obj == null || !(obj instanceof Person)) return false;
+            Person p = (Person) obj;
+            return equals(name, p.name) && p.gender == gender && equals(address, p.address);
+        }
+
+        private boolean equals(final Object o1, final Object o2) {
+            return o1 == o2 || (o1 != null && o1.equals(o2));
+        }
+    }
+}
\ No newline at end of file

utilcode/build.gradle

@@ -35,6 +35,7 @@ android {
 dependencies {
     compileOnly "com.android.support:appcompat-v7:$support_version"
     compileOnly "com.android.support:design:$support_version"
+
     testImplementation "junit:junit:$junit_version"
     testImplementation "org.robolectric:robolectric:$robolectric_version"
     testImplementation "com.android.support:support-v4:$support_version"