Fix build failure with JDK 11.0.2.

Signed-off-by: leadpony <[email protected]>

Author: leadpony

api/pom.xml

@@ -65,9 +65,6 @@
     <br>Comments to : [email protected]
 ]]>
                     </bottom>
-                    <links>
-                        <link>http://docs.oracle.com/javase/8/docs/api/</link>
-                    </links>
                 </configuration>
 
                 <executions>

demos/customprovider-jdk9/pom.xml

@@ -52,7 +52,6 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-surefire-plugin</artifactId>
-                <version>2.20</version>
                 <executions>
                     <execution>
                         <goals>

pom.xml

@@ -79,6 +79,7 @@
         <new_impl_version>1.2.0</new_impl_version>
         <non.final>false</non.final>
         <legal.doc.source>${maven.multiModuleProjectDirectory}</legal.doc.source>
+        <javadoc.link.jdk>http://docs.oracle.com/javase/8/docs/api</javadoc.link.jdk>
     </properties>
 
     <build>
@@ -178,6 +179,12 @@
                     <groupId>org.apache.maven.plugins</groupId>
                     <artifactId>maven-javadoc-plugin</artifactId>
                     <version>3.0.1</version>
+                    <configuration>
+                        <detectJavaApiLink>false</detectJavaApiLink>
+                        <links>
+                            <link>${javadoc.link.jdk}</link>
+                        </links>
+                    </configuration>
                 </plugin>
                 <plugin>
                     <groupId>org.apache.maven.plugins</groupId>
@@ -366,6 +373,7 @@
                             <groupId>org.apache.maven.plugins</groupId>
                             <artifactId>maven-compiler-plugin</artifactId>
                             <configuration>
+                                <source>8</source>
                                 <release>8</release>
                             </configuration>
                             <executions>
@@ -431,6 +439,16 @@
             </modules>
         </profile>
 
+        <profile>
+            <id>jdk11-setup</id>
+            <activation>
+                <jdk>[11,)</jdk>
+            </activation>
+            <properties>
+                <javadoc.link.jdk>https://docs.oracle.com/en/java/javase/11/docs/api</javadoc.link.jdk>
+            </properties>
+        </profile>
+
         <profile>
             <id>all</id>
             <activation>