use add-opens to allow serialization of java.time.Duration

Author: diegomarquezp

google-cloud-logging/src/main/java/com/google/cloud/logging/LogEntry.java

@@ -34,7 +34,6 @@
 import com.google.logging.v2.LogEntrySourceLocation;
 import com.google.logging.v2.LogName;
 import java.io.Serializable;
-import java.time.Duration;
 import java.time.Instant;
 import java.util.HashMap;
 import java.util.Map;
@@ -613,14 +612,6 @@ public JsonElement serialize(
     }
   }
 
-  static final class DurationSerializer implements JsonSerializer<Duration> {
-    @Override
-    public JsonElement serialize(
-        Duration src, java.lang.reflect.Type typeOfSrc, JsonSerializationContext context) {
-      return new JsonPrimitive(src.toString());
-    }
-  }
-
   static final class SourceLocationSerializer implements JsonSerializer<SourceLocation> {
     @Override
     public JsonElement serialize(
@@ -658,7 +649,6 @@ public StructuredLogFormatter(StringBuilder builder) {
       checkNotNull(builder);
       this.gson =
           new GsonBuilder()
-              .registerTypeAdapter(Duration.class, new DurationSerializer())
               .registerTypeAdapter(Instant.class, new InstantSerializer())
               .registerTypeAdapter(SourceLocation.class, new SourceLocationSerializer())
               .registerTypeAdapter(HttpRequest.RequestMethod.class, new RequestMethodSerializer())

pom.xml

@@ -197,6 +197,38 @@
             <ignoredUnusedDeclaredDependencies>org.objenesis:objenesis</ignoredUnusedDeclaredDependencies>
           </configuration>
         </plugin>
+        <plugin>
+          <groupId>org.apache.maven.plugins</groupId>
+          <artifactId>maven-jar-plugin</artifactId>
+          <executions>
+            <execution>
+              <id>default-jar</id>
+              <phase>package</phase>
+              <goals>
+                <goal>jar</goal>
+              </goals>
+              <configuration>
+                <archive>
+                  <manifestEntries>
+                    <!-- This manifest entry is ignored by java 8.
+                    It allows inter-module access when Gson serializes
+                    the private variables of java.time.Duration -->
+                    <Add-Opens>java.base/java.time=ALL-UNNAMED</Add-Opens>
+                  </manifestEntries>
+                </archive>
+              </configuration>
+            </execution>
+          </executions>
+        </plugin>
+        <plugin>
+          <groupId>org.apache.maven.plugins</groupId>
+          <artifactId>maven-surefire-plugin</artifactId>
+          <configuration>
+            <!-- This arg line allows inter-module access when Gson serializes
+            the private variables of java.time.Duration -->
+            <argLine>--add-opens java.base/java.time=ALL-UNNAMED</argLine>
+          </configuration>
+        </plugin>
       </plugins>
     </pluginManagement>
   </build>