Adjust pom.xml to facilitate deployment

Follow advice at https://central.sonatype.org/publish/publish-maven/
to deploy the package to the central repository.

Various changes needed including changing the groupId since I have
publish permissions for uk.ac.starlink but not for org.astrogrid.

mvn deploy now seems to work to deploy the package to central.sonatype.com.

It is also possible to do the deployment manually.
I've added a hints.txt file to explain how that is currently done.

Make a few cosmetic changes too.

hints.txt

@@ -0,0 +1,58 @@
+Notes:
+------
+   mvn clean
+   mvn package
+   mvn site
+   mvn -DskipTests
+
+On release:
+-----------
+
+(I'm pretty sure I'm comprehensively missing the point of maven by
+having to do this manually).
+
+update version number in pom.xml in TWO places:
+   <project>/<version>
+   <project>/<properties>/<jsampVersion>
+
+mvn clean package site install
+
+# 2024 I no longer have a code-signing certificate, so can't do this.
+jarsigner 
+   -keystore /home/mbt/certs/comodo-uob.p12
+   -storetype pkcs12
+   -tsa http://timestamp.comodoca.com
+   -signedjar target/jsamp-${pom.currentVersion}_signed.jar
+   target/jsamp-${pom.currentVersion}.jar
+   uob
+
+cp target/jsamp-x.x.x.jar /home/mbt/public_html/releases/jsamp/
+
+rm -rf /home/mbt/public_html/jsamp
+mkdir /home/mbt/public_html/jsamp
+cp target/jsamp-x.x.x.jar /home/mbt/public_html/jsamp/
+cp -r target/site/* /home/mbt/public_html/jsamp
+
+tag and add jar file to github release
+
+# mvn deploy seems to work to deploy the thing to the central repo
+# at https://central.sonatype.com/search?q=g:uk.ac.starlink
+# I followed instructions at
+# https://central.sonatype.org/publish/publish-maven/
+# This can also be done manually in the same way as for
+# /mbt/devel/stil/makefile, as below.
+
+mvn gpg:sign-and-deploy-file -Durl=https://s01.oss.sonatype.org/service/local/staging/deploy/maven2/ -DrepositoryId=ossrh -DpomFile=pom.xml -Dfile=target/jsamp-x.x.x.jar
+mvn gpg:sign-and-deploy-file -Durl=https://s01.oss.sonatype.org/service/local/staging/deploy/maven2/ -DrepositoryId=ossrh -DpomFile=pom.xml -Dfile=target/jsamp-x.x.x-sources.jar -Dclassifier=sources
+mvn gpg:sign-and-deploy-file -Durl=https://s01.oss.sonatype.org/service/local/staging/deploy/maven2/ -DrepositoryId=ossrh -DpomFile=pom.xml -Dfile=target/jsamp-x.x.x-javadoc.jar -Dclassifier=javadoc
+
+# This uses ~/.m2/settings.xml, which looks like:
+<settings>
+  <servers>
+    <server>
+      <id>ossrh</id>
+      <username>mbtaylor</username>
+      <password>xxx</password>
+    </server>
+  </servers>
+</settings>

pom.xml

@@ -4,14 +4,21 @@
          xmlns="http://maven.apache.org/POM/4.0.0"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
   <modelVersion>4.0.0</modelVersion>
-  <groupId>org.astrogrid</groupId>
+  <groupId>uk.ac.starlink</groupId>
   <artifactId>jsamp</artifactId>
   <version>1.3.8</version>
   <name>JSAMP</name>
-  <url>http://www.star.bristol.ac.uk/~mbt/jsamp/</url>
+  <url>http://www.star.bristol.ac.uk/mbt/jsamp/</url>
+  <licenses>
+    <license>
+      <name>The Apache License, Version 2.0</name>
+      <url>http://www.apache.org/licenses/LICENSE-2.0.txt</url>
+    </license>
+  </licenses>
   <scm>
     <connection>scm:git:https://github.com/mbtaylor/jsamp.git</connection>
     <developerConnection>scm:git:git@github.com:mbtaylor/jsamp.git</developerConnection>
+    <url>https://github.com/mbtaylor/jsamp/tree/master</url>
   </scm>
   <description>Various components used for developing and deploying
     Simple Applications Messaging Protocol-compliant 
@@ -23,8 +30,8 @@
       <id>mbt</id>
       <name>Mark Taylor</name>
       <email>m.b.taylor@bristol.ac.uk</email>
-      <url>http://www.star.bristol.ac.uk/~mbt/</url>
-      <organization>Bristol University</organization>
+      <url>http://www.star.bristol.ac.uk/mbt/</url>
+      <organization>University of Bristol</organization>
     </developer>
   </developers>
 
@@ -52,7 +59,7 @@
        !   (or anything else).
        !   Currently I'm doing that copying by hand when releasing
        !   a new version. -->
-      <url>file:///homeb/mbt/public_html/jsamp/</url>
+      <url>file:///home/mbt/public_html/jsamp/</url>
     </site>
   </distributionManagement>
 
@@ -168,8 +175,61 @@
       </plugin>
 
       <plugin>
-        <artifactId>maven-deploy-plugin</artifactId>
-        <version>2.8.1</version>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-source-plugin</artifactId>
+        <version>2.2.1</version>
+        <executions>
+          <execution>
+            <id>attach-sources</id>
+            <goals>
+              <goal>jar-no-fork</goal>
+            </goals>
+          </execution>
+        </executions>
+      </plugin>
+
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-javadoc-plugin</artifactId>
+        <version>2.9.1</version>
+        <configuration>
+          <additionalparam>-Xdoclint:none</additionalparam>
+        </configuration>
+        <executions>
+          <execution>
+            <id>attach-javadocs</id>
+            <goals>
+              <goal>jar</goal>
+            </goals>
+          </execution>
+        </executions>
+      </plugin>
+
+      <plugin>
+        <groupId>org.sonatype.plugins</groupId>
+        <artifactId>nexus-staging-maven-plugin</artifactId>
+        <version>1.6.7</version>
+        <extensions>true</extensions>
+        <configuration>
+           <serverId>ossrh</serverId>
+           <nexusUrl>https://s01.oss.sonatype.org/</nexusUrl>
+           <autoReleaseAfterClose>false</autoReleaseAfterClose>
+        </configuration>
+      </plugin>
+
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-gpg-plugin</artifactId>
+        <version>1.5</version>
+        <executions>
+          <execution>
+            <id>sign-artifacts</id>
+            <phase>verify</phase>
+            <goals>
+              <goal>sign</goal>
+            </goals>
+          </execution>
+        </executions>
       </plugin>
 
     </plugins>