Suppress this-escape warning for JDK21

modules/apm/src/main/java/org/elasticsearch/telemetry/apm/AbstractInstrument.java

@@ -30,6 +30,7 @@ public abstract class AbstractInstrument<T> implements Instrument {
     private final String description;
     private final String unit;
 
+    @SuppressWarnings("this-escape")
     public AbstractInstrument(Meter meter, String name, String description, String unit) {
         this.name = Objects.requireNonNull(name);
         this.description = Objects.requireNonNull(description);

server/src/main/java/org/elasticsearch/action/search/SearchResponse.java

@@ -538,6 +538,7 @@ public Clusters(int total, int successful, int skipped) {
             this.clusterInfo = Collections.emptyMap();  // will never be used if created from this constructor
         }
 
+        @SuppressWarnings("this-escape")
         public Clusters(StreamInput in) throws IOException {
             this.total = in.readVInt();
             int successfulTemp = in.readVInt();

server/src/main/java/org/elasticsearch/action/support/HandledTransportAction.java

@@ -31,6 +31,7 @@ protected HandledTransportAction(
         this(actionName, true, transportService, actionFilters, requestReader, executor);
     }
 
+    @SuppressWarnings("this-escape")
     protected HandledTransportAction(
         String actionName,
         boolean canTripCircuitBreaker,

server/src/main/java/org/elasticsearch/action/support/nodes/TransportNodesAction.java

@@ -87,6 +87,7 @@ protected TransportNodesAction(
      * @deprecated Use the local-only constructor instead.
      */
     @Deprecated(forRemoval = true)
+    @SuppressWarnings("this-escape")
     protected TransportNodesAction(
         String actionName,
         ThreadPool threadPool,

x-pack/plugin/esql/build.gradle

@@ -197,6 +197,23 @@ tasks.register("regen") {
     ant.replaceregexp(match: '\t', flags: 'g', replace: '  ', encoding: 'UTF-8') {
       fileset(dir: outputPath, includes: 'EsqlBase*.java')
     }
+    // suppress this-escape warnings on EsqlBaseLexer
+    ant.replaceregexp(
+      match: 'public EsqlBaseLexer',
+      replace: '@SuppressWarnings("this-escape")${line.separator}  public EsqlBaseLexer',
+      encoding: 'UTF-8'
+    ) {
+      fileset(dir: outputPath, includes: 'EsqlBaseLexer.java')
+    }
+    // suppress this-escape warnings on all internal EsqlBaseParser class constructores
+    ant.replaceregexp(
+      match: '([ ]+)public ([A-Z][a-z]+[a-z,A-Z]+\\()',
+      flags: 'g',
+      replace: '\\1@SuppressWarnings("this-escape")${line.separator}\\1public \\2',
+      encoding: 'UTF-8'
+    ) {
+      fileset(dir: outputPath, includes: 'EsqlBaseParser.java')
+    }
     // fix line endings
     ant.fixcrlf(srcdir: outputPath, eol: 'lf') {
       patternset(includes: 'EsqlBase*.java')

x-pack/plugin/esql/compute/src/main/java/org/elasticsearch/compute/data/DocVector.java

@@ -48,6 +48,7 @@ public class DocVector extends AbstractVector implements Vector {
 
     final DocBlock block;
 
+    @SuppressWarnings("this-escape")
     public DocVector(IntVector shards, IntVector segments, IntVector docs, Boolean singleSegmentNonDecreasing) {
         super(shards.getPositionCount(), null);
         this.shards = shards;

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/parser/EsqlBaseLexer.java

@@ -127,6 +127,7 @@ public Vocabulary getVocabulary() {
   }
 
 
+  @SuppressWarnings("this-escape")
   public EsqlBaseLexer(CharStream input) {
     super(input);
     _interp = new LexerATNSimulator(this,_ATN,_decisionToDFA,_sharedContextCache);