fix [this-escape] warnings by declaring classes final.

Origin: upstream, 48935be468
Bug: https://bugs.openjdk.org/browse/CODETOOLS-7903516
Bug-Debian: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1057511
Forwarded: not-needed
Applied-Upstream: 48935be4685ec5c99b3fe15c10439946944c9f7e

[this-escape] warning is generated when a class's constructor calls
a method that can be overridden.

Gbp-Pq: Name java21-this-escape.patch

src/share/classes/com/sun/javatest/regtest/agent/AgentServer.java

@@ -57,7 +57,7 @@ import java.util.concurrent.TimeUnit;
 
 
 @SuppressWarnings("removal") // Security Manager and related APIs
-public class AgentServer implements ActionHelper.OutputHandler {
+public final class AgentServer implements ActionHelper.OutputHandler {
 
     /**
      * Main program used to invoke and run the server in child JVMs

src/share/classes/com/sun/javatest/regtest/agent/SearchPath.java

@@ -37,7 +37,7 @@ import java.util.regex.Pattern;
  * A path, as in an ordered set of file system locations, such as directories,
  * zip files and jar files.
  */
-public class SearchPath {
+public final class SearchPath {
     /**
      * Create an empty path.
      */

src/share/classes/com/sun/javatest/regtest/config/Locations.java

@@ -44,7 +44,7 @@ import com.sun.javatest.regtest.util.StringUtils;
 /**
  * Utilities to locate source and class files used by a test.
  */
-public class Locations {
+public final class Locations {
     /**
      * Used to report problems that are found.
      */

src/share/classes/com/sun/javatest/regtest/config/ParseException.java

@@ -34,7 +34,7 @@ import com.sun.javatest.regtest.exec.TestRunException;
  *
  * @author Iris A Garcia
  */
-public class ParseException extends TestRunException
+public final class ParseException extends TestRunException
 {
     static final long serialVersionUID = 5598548899306920122L;
     public ParseException(String msg) {
@@ -44,7 +44,7 @@ public class ParseException extends TestRunException
     public ParseException(Throwable t) {
         super(PARSE_EXCEPTION + t.getMessage());
         initCause(t);
-    } // ParseExeptionException()
+    }
 
     //----------misc statics----------------------------------------------------
 

src/share/classes/com/sun/javatest/regtest/config/RegressionParameters.java

@@ -65,7 +65,7 @@ import com.sun.javatest.regtest.util.StringUtils;
 import static com.sun.javatest.regtest.util.StringUtils.join;
 
 
-public class RegressionParameters
+public final class RegressionParameters
     extends BasicInterviewParameters
     implements Parameters.EnvParameters
 {

src/share/classes/com/sun/javatest/regtest/config/RegressionTestFinder.java

@@ -66,7 +66,7 @@ import com.sun.javatest.util.I18NResourceBundle;
   * @see com.sun.javatest.TestFinder
   * @see com.sun.javatest.finder.TagTestFinder
   */
-public class RegressionTestFinder extends TagTestFinder
+public final class RegressionTestFinder extends TagTestFinder
 {
     /**
      * Constructs the list of file names to exclude for pruning in the search

src/share/classes/com/sun/javatest/regtest/config/RegressionTestSuite.java

@@ -51,7 +51,7 @@ import com.sun.javatest.util.I18NResourceBundle;
 import com.sun.javatest.regtest.tool.RegressionContextManager;
 
 
-public class RegressionTestSuite extends TestSuite
+public final class RegressionTestSuite extends TestSuite
 {
     static Map<File, SoftReference<RegressionTestSuite>> cache;
 

src/share/classes/com/sun/javatest/regtest/util/StreamCopier.java

@@ -34,7 +34,7 @@ import java.io.PrintWriter;
 /**
  * A thread to copy an input stream/reader to an output stream/writer.
  */
-public class StreamCopier extends Thread {
+public final class StreamCopier extends Thread {
 
     public StreamCopier(InputStream in, PrintWriter out, LineScanner scanner) {
         super(Thread.currentThread().getName() + "_StreamCopier_" + (serial++));