Enforce -release 8 base compilation target (#2250)

Set -release 8 base compilation target

Restructured the compile phases in the POM so that when executing on Java 9+, the base classes are compiled with -release 8. This ensures that the bootstrap class path uses the Java 8 API, and so the produced jar is binary compat with Java 8.

When built on Java 8, the original source and target (vs release) are used.

Fixes an issue where when running on Java 8 (but built on Java9+),  `java.lang.NoSuchMethodError: java.nio.ByteBuffer.flip()Ljava/nio/ByteBuffer;` would be thrown in ControllableInputStream buffering up, because the return expected `Buffer`, not the binary incompatible `ByteBuffer`.

Author: jhy

CHANGES.md

@@ -33,6 +33,9 @@
   "name". [2241](https://github.com/jhy/jsoup/issues/2241)
 * In `Connection`, skip cookies that have no name, rather than throwing a validation
   exception. [2242](https://github.com/jhy/jsoup/issues/2242)
+* When running on JDK 1.8, the error `java.lang.NoSuchMethodError: java.nio.ByteBuffer.flip()Ljava/nio/ByteBuffer;`
+  could be thrown when parsing from a URL and the buffer size was
+  exceeded. [2250](https://github.com/jhy/jsoup/pull/2250)
 
 ## 1.18.3 (2024-Dec-02)
 

pom.xml

@@ -38,29 +38,27 @@
 
   <build>
     <plugins>
-      <!-- Compile -->
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-compiler-plugin</artifactId>
         <version>3.13.0</version>
         <configuration>
           <encoding>UTF-8</encoding>
+          <useIncrementalCompilation>false</useIncrementalCompilation>
           <compilerArgs>
-            <!-- saves output for package-info.java, so mvn sees it has completed it, so incremental compile works -->
             <arg>-Xpkginfo:always</arg>
           </compilerArgs>
-          <!-- this means incremental = true... -->
-          <useIncrementalCompilation>false</useIncrementalCompilation>
         </configuration>
         <executions>
+          <!-- Disable the default compile, so the profiles activated below execute -->
           <execution>
-            <id>compile-java-8</id>
-            <configuration>
-              <source>1.8</source>
-              <target>1.8</target>
-            </configuration>
+            <id>default-compile</id>
+            <phase>none</phase>
+          </execution>
+          <execution>
+            <id>default-testCompile</id>
+            <phase>none</phase>
           </execution>
-          <!-- There is a JDK 9+ profile execution below, which adds multi-release=true and compiles module-info -->
         </executions>
       </plugin>
 
@@ -83,7 +81,6 @@
                 <version>1.0</version>
               </signature>
               <ignores>
-                <ignore>java.nio.ByteBuffer</ignore> <!-- .flip(); added in API1; possibly due to .flip previously returning Buffer, later ByteBuffer; return unused -->
                 <ignore>java.net.HttpURLConnection</ignore><!-- .setAuthenticator(java.net.Authenticator) in Java 9; only used in multirelease 9+ version -->
               </ignores>
             </configuration>
@@ -292,7 +289,7 @@
             <excludes>
               <!-- <exclude>@java.lang.Deprecated</exclude> -->
               <exclude>org.jsoup.UncheckedIOException</exclude>
-              <exlude>org.jsoup.nodes.Element</exlude> <!-- forEach previously deprecated -->
+              <exclude>org.jsoup.nodes.Element</exclude> <!-- forEach previously deprecated -->
             </excludes>
             <overrideCompatibilityChangeParameters>
               <!-- allows new default and move to default methods. compatible as long as existing binaries aren't making calls via reflection. if so, they need to catch errors anyway. -->
@@ -345,6 +342,36 @@
   </distributionManagement>
 
   <profiles>
+    <!-- Profile for Java 8 -->
+    <profile>
+      <id>java-8</id>
+      <activation>
+        <jdk>1.8</jdk>
+      </activation>
+      <build>
+        <plugins>
+          <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-compiler-plugin</artifactId>
+            <executions>
+              <execution>
+                <id>compile</id>
+                <phase>compile</phase>
+                <goals>
+                  <goal>compile</goal>
+                  <goal>testCompile</goal>
+                </goals>
+                <configuration>
+                  <source>1.8</source>
+                  <target>1.8</target>
+                </configuration>
+              </execution>
+            </executions>
+          </plugin>
+        </plugins>
+      </build>
+    </profile>
+
     <!-- Compiles the multi-release jar when executed on JDK9+ -->
     <profile>
       <id>compile-multi-release</id>
@@ -357,12 +384,19 @@
             <groupId>org.apache.maven.plugins</groupId>
             <artifactId>maven-compiler-plugin</artifactId>
             <executions>
+
               <execution>
                 <id>compile-java-8</id>
+                <phase>compile</phase>
+                <goals>
+                  <goal>compile</goal>
+                  <goal>testCompile</goal>
+                </goals>
                 <configuration>
                   <release>8</release>
                 </configuration>
               </execution>
+
               <execution>
                 <id>compile-java-9</id>
                 <phase>compile</phase>
@@ -377,6 +411,7 @@
                   <multiReleaseOutput>true</multiReleaseOutput>
                 </configuration>
               </execution>
+
             </executions>
           </plugin>
         </plugins>