initial commit for java 21

build.gradle

@@ -73,7 +73,7 @@ ext {
   }
 
   // Minimum Java version required to compile and run Lucene.
-  minJavaVersion = JavaVersion.VERSION_17
+  minJavaVersion = JavaVersion.VERSION_21
 
   // snapshot build marker used in scripts.
   snapshotBuild = version.contains("SNAPSHOT")
@@ -101,6 +101,12 @@ dependencies {
   groovy "org.codehaus.groovy:groovy-all:3.0.12"
 }
 
+repositories {
+  maven {
+    url "https://repo.eclipse.org/content/repositories/eclipse-snapshots/"
+  }
+}
+
 apply from: file('buildSrc/scriptDepVersions.gradle')
 
 // Include smaller chunks configuring dedicated build areas.

buildSrc/scriptDepVersions.gradle

@@ -24,7 +24,7 @@ ext {
       "apache-rat": "0.14",
       "asm": "9.6",
       "commons-codec": "1.13",
-      "ecj": "3.30.0",
+      "ecj": "3.36.0-SNAPSHOT",
       "flexmark": "0.61.24",
       "javacc": "7.0.12",
       "jflex": "1.8.2",

lucene/analysis/common/src/java/org/apache/lucene/analysis/br/BrazilianStemmer.java

@@ -20,7 +20,7 @@ import java.util.Locale;
 
 /** A stemmer for Brazilian Portuguese words. */
 class BrazilianStemmer {
-  private static final Locale locale = new Locale("pt", "BR");
+  private static final Locale locale = Locale.of("pt", "BR");
 
   /** Changed term */
   private String TERM;

lucene/analysis/common/src/java/org/apache/lucene/analysis/de/GermanStemmer.java

@@ -33,7 +33,7 @@ class GermanStemmer {
   /** Amount of characters that are removed with <code>substitute()</code> while stemming. */
   private int substCount = 0;
 
-  private static final Locale locale = new Locale("de", "DE");
+  private static final Locale locale = Locale.of("de", "DE");
 
   /**
    * Stemms the given term to an unique <code>discriminator</code>.

lucene/analysis/common/src/java/org/apache/lucene/analysis/th/ThaiTokenizer.java

@@ -38,7 +38,7 @@ public class ThaiTokenizer extends SegmentingTokenizerBase {
    */
   public static final boolean DBBI_AVAILABLE;
 
-  private static final BreakIterator proto = BreakIterator.getWordInstance(new Locale("th"));
+  private static final BreakIterator proto = BreakIterator.getWordInstance(Locale.of("th"));
 
   static {
     // check that we have a working dictionary-based break iterator for thai

lucene/analysis/common/src/test/org/apache/lucene/collation/TestCollationKeyAnalyzer.java

@@ -26,7 +26,7 @@ public class TestCollationKeyAnalyzer extends CollationTestBase {
   // Neither Java 1.4.2 nor 1.5.0 has Farsi Locale collation available in
   // RuleBasedCollator.  However, the Arabic Locale seems to order the Farsi
   // characters properly.
-  private Collator collator = Collator.getInstance(new Locale("ar"));
+  private Collator collator = Collator.getInstance(Locale.of("ar"));
   private Analyzer analyzer;
 
   @Override

lucene/analysis/common/src/tools/java/org/apache/lucene/analysis/standard/GenerateJflexTLDMacros.java

@@ -21,6 +21,7 @@ import java.io.IOException;
 import java.io.InputStreamReader;
 import java.io.OutputStreamWriter;
 import java.io.Writer;
+import java.net.URI;
 import java.net.URL;
 import java.net.URLConnection;
 import java.nio.charset.StandardCharsets;
@@ -111,7 +112,7 @@ public class GenerateJflexTLDMacros {
 
   public GenerateJflexTLDMacros(String tldFileURL, String jflexFile, String tldListFile)
       throws Exception {
-    this.tldFileURL = new URL(tldFileURL);
+    this.tldFileURL = URI.create(tldFileURL).toURL();
     this.jflexMacroFile = Paths.get(jflexFile);
     this.tldListFile = Paths.get(tldListFile);
   }

lucene/analysis/icu/src/test/org/apache/lucene/analysis/icu/TestICUCollationKeyAnalyzer.java

@@ -24,7 +24,7 @@ import org.apache.lucene.util.BytesRef;
 
 public class TestICUCollationKeyAnalyzer extends CollationTestBase {
 
-  private Collator collator = Collator.getInstance(new Locale("fa"));
+  private Collator collator = Collator.getInstance(Locale.of("fa"));
   private Analyzer analyzer;
 
   @Override

lucene/analysis/icu/src/tools/java/org/apache/lucene/analysis/icu/GenerateUTR30DataFiles.java

@@ -27,6 +27,7 @@ import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
 import java.io.Writer;
+import java.net.URI;
 import java.net.URL;
 import java.net.URLConnection;
 import java.nio.charset.StandardCharsets;
@@ -155,19 +156,19 @@ public class GenerateUTR30DataFiles {
   }
 
   private static void getNFKCDataFilesFromIcuProject(String releaseTag) throws IOException {
-    URL icuTagsURL = new URL(ICU_GIT_TAG_URL + "/");
+    URI icuTagsURL = URI.create(ICU_GIT_TAG_URL + "/");
-    URL icuReleaseTagURL = new URL(icuTagsURL, releaseTag + "/");
+    URI icuReleaseTagURL = icuTagsURL.resolve(releaseTag + "/");
-    URL norm2url = new URL(icuReleaseTagURL, ICU_DATA_NORM2_PATH + "/");
+    URI norm2url = icuReleaseTagURL.resolve(ICU_DATA_NORM2_PATH + "/");
 
     System.err.print("Downloading " + NFKC_TXT + " ... ");
-    download(new URL(norm2url, NFKC_TXT), NFKC_TXT);
+    download(norm2url.resolve(NFKC_TXT), NFKC_TXT);
     System.err.println("done.");
     System.err.print("Downloading " + NFKC_CF_TXT + " ... ");
-    download(new URL(norm2url, NFKC_CF_TXT), NFKC_CF_TXT);
+    download(norm2url.resolve(NFKC_CF_TXT), NFKC_CF_TXT);
     System.err.println("done.");
 
     System.err.print("Downloading " + NFKC_CF_TXT + " and making diacritic rules one-way ... ");
-    URLConnection connection = openConnection(new URL(norm2url, NFC_TXT));
+    URLConnection connection = openConnection(norm2url.resolve(NFC_TXT).toURL());
     try (BufferedReader reader =
             new BufferedReader(
                 new InputStreamReader(connection.getInputStream(), StandardCharsets.UTF_8));
@@ -210,8 +211,8 @@ public class GenerateUTR30DataFiles {
     System.err.println("done.");
   }
 
-  private static void download(URL url, String outputFile) throws IOException {
+  private static void download(URI uri, String outputFile) throws IOException {
-    final URLConnection connection = openConnection(url);
+    final URLConnection connection = openConnection(uri.toURL());
     try (InputStream inputStream = connection.getInputStream();
         OutputStream outputStream = Files.newOutputStream(Path.of(outputFile))) {
       inputStream.transferTo(outputStream);

lucene/benchmark/src/java/org/apache/lucene/benchmark/byTask/PerfRunData.java

@@ -46,6 +46,7 @@ import org.apache.lucene.store.ByteBuffersDirectory;
 import org.apache.lucene.store.Directory;
 import org.apache.lucene.store.FSDirectory;
 import org.apache.lucene.util.IOUtils;
+import org.apache.lucene.util.SuppressForbidden;
 
 /**
  * Data maintained by a performance test run.
@@ -204,7 +205,7 @@ public class PerfRunData implements Closeable {
     resetInputs();
 
     // release unused stuff
-    System.runFinalization();
+    runFinalization();
     System.gc();
 
     // Re-init clock
@@ -482,4 +483,10 @@ public class PerfRunData implements Closeable {
   public Map<String, AnalyzerFactory> getAnalyzerFactories() {
     return analyzerFactories;
   }
+
+  @SuppressWarnings("removal")
+  @SuppressForbidden(reason = "requires to run finalization")
+  private static void runFinalization() {
+    System.runFinalization();
+  }
 }

lucene/benchmark/src/java/org/apache/lucene/benchmark/byTask/tasks/NewLocaleTask.java

@@ -39,7 +39,7 @@ public class NewLocaleTask extends PerfTask {
   private String variant;
 
   /**
-   * Create a new {@link java.util.Locale} and set it it in the getRunData() for use by all future
+   * Create a new {@link java.util.Locale} and set it in the getRunData() for use by all future
    * tasks.
    */
   public NewLocaleTask(PerfRunData runData) {
@@ -52,7 +52,7 @@ public class NewLocaleTask extends PerfTask {
     String lang = language;
     if (lang.equalsIgnoreCase("ROOT")) lang = ""; // empty language is the root locale in the JDK
 
-    return new Locale(lang, country, variant);
+    return Locale.of(lang, country, variant);
   }
 
   @Override

lucene/benchmark/src/test/org/apache/lucene/benchmark/byTask/TestPerfTasksLogic.java

@@ -793,19 +793,19 @@ public class TestPerfTasksLogic extends BenchmarkTestCase {
 
     // ROOT locale
     benchmark = execBenchmark(getLocaleConfig("ROOT"));
-    assertEquals(new Locale(""), benchmark.getRunData().getLocale());
+    assertEquals(Locale.of(""), benchmark.getRunData().getLocale());
 
     // specify just a language
     benchmark = execBenchmark(getLocaleConfig("de"));
-    assertEquals(new Locale("de"), benchmark.getRunData().getLocale());
+    assertEquals(Locale.of("de"), benchmark.getRunData().getLocale());
 
     // specify language + country
     benchmark = execBenchmark(getLocaleConfig("en,US"));
-    assertEquals(new Locale("en", "US"), benchmark.getRunData().getLocale());
+    assertEquals(Locale.of("en", "US"), benchmark.getRunData().getLocale());
 
     // specify language + country + variant
     benchmark = execBenchmark(getLocaleConfig("no,NO,NY"));
-    assertEquals(new Locale("no", "NO", "NY"), benchmark.getRunData().getLocale());
+    assertEquals(Locale.of("no", "NO", "NY"), benchmark.getRunData().getLocale());
   }
 
   private String[] getLocaleConfig(String localeParam) {
@@ -832,22 +832,22 @@ public class TestPerfTasksLogic extends BenchmarkTestCase {
   public void testCollator() throws Exception {
     // ROOT locale
     Benchmark benchmark = execBenchmark(getCollatorConfig("ROOT", "impl:jdk"));
-    CollationKeyAnalyzer expected = new CollationKeyAnalyzer(Collator.getInstance(new Locale("")));
+    CollationKeyAnalyzer expected = new CollationKeyAnalyzer(Collator.getInstance(Locale.of("")));
     assertEqualCollation(expected, benchmark.getRunData().getAnalyzer(), "foobar");
 
     // specify just a language
     benchmark = execBenchmark(getCollatorConfig("de", "impl:jdk"));
-    expected = new CollationKeyAnalyzer(Collator.getInstance(new Locale("de")));
+    expected = new CollationKeyAnalyzer(Collator.getInstance(Locale.of("de")));
     assertEqualCollation(expected, benchmark.getRunData().getAnalyzer(), "foobar");
 
     // specify language + country
     benchmark = execBenchmark(getCollatorConfig("en,US", "impl:jdk"));
-    expected = new CollationKeyAnalyzer(Collator.getInstance(new Locale("en", "US")));
+    expected = new CollationKeyAnalyzer(Collator.getInstance(Locale.of("en", "US")));
     assertEqualCollation(expected, benchmark.getRunData().getAnalyzer(), "foobar");
 
     // specify language + country + variant
     benchmark = execBenchmark(getCollatorConfig("no,NO,NY", "impl:jdk"));
-    expected = new CollationKeyAnalyzer(Collator.getInstance(new Locale("no", "NO", "NY")));
+    expected = new CollationKeyAnalyzer(Collator.getInstance(Locale.of("no", "NO", "NY")));
     assertEqualCollation(expected, benchmark.getRunData().getAnalyzer(), "foobar");
   }
 

lucene/benchmark/src/test/org/apache/lucene/benchmark/byTask/feeds/TestHtmlParser.java

@@ -96,7 +96,7 @@ public class TestHtmlParser extends LuceneTestCase {
   public void testTurkish() throws Exception {
     final Locale saved = Locale.getDefault();
     try {
-      Locale.setDefault(new Locale("tr", "TR"));
+      Locale.setDefault(Locale.of("tr", "TR"));
       String text =
           "<html><HEAD><TITLE>ııı</TITLE></head><body>"
               + "<IMG SRC=\"../images/head.jpg\" WIDTH=570 HEIGHT=47 BORDER=0 ALT=\"ş\">"

lucene/core/src/test/org/apache/lucene/util/TestWeakIdentityMap.java

@@ -119,7 +119,7 @@ public class TestWeakIdentityMap extends LuceneTestCase {
     int size = map.size();
     for (int i = 0; size > 0 && i < 10; i++)
       try {
-        System.runFinalization();
+        runFinalization();
         System.gc();
         int newSize = map.size();
         assertTrue("previousSize(" + size + ")>=newSize(" + newSize + ")", size >= newSize);
@@ -232,7 +232,7 @@ public class TestWeakIdentityMap extends LuceneTestCase {
     int size = map.size();
     for (int i = 0; size > 0 && i < 10; i++)
       try {
-        System.runFinalization();
+        runFinalization();
         System.gc();
         int newSize = map.size();
         assertTrue("previousSize(" + size + ")>=newSize(" + newSize + ")", size >= newSize);
@@ -252,4 +252,10 @@ public class TestWeakIdentityMap extends LuceneTestCase {
           InterruptedException ie) {
       }
   }
+
+  @SuppressWarnings("removal")
+  @SuppressForbidden(reason = "requires to run finalization")
+  private static void runFinalization() {
+    System.runFinalization();
+  }
 }

lucene/luke/src/java/org/apache/lucene/luke/app/desktop/components/fragments/search/QueryParserPaneProvider.java

@@ -421,7 +421,7 @@ public final class QueryParserPaneProvider implements QueryParserTabOperator {
         .fuzzyMinSim(fuzzyMinSimFloat)
         .fuzzyPrefixLength(fuzzyPrefLenInt)
         .dateResolution(DateTools.Resolution.valueOf((String) dateResCB.getSelectedItem()))
-        .locale(new Locale(locationTF.getText()))
+        .locale(Locale.of(locationTF.getText()))
         .timeZone(TimeZone.getTimeZone(timezoneTF.getText()))
         .typeMap(typeMap)
         .build();

lucene/luke/src/java/org/apache/lucene/luke/app/desktop/util/URLLabel.java

@@ -23,6 +23,7 @@ import java.awt.event.MouseAdapter;
 import java.awt.event.MouseEvent;
 import java.io.IOException;
 import java.net.MalformedURLException;
+import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
 import javax.swing.JLabel;
@@ -37,7 +38,7 @@ public final class URLLabel extends JLabel {
     super(text);
 
     try {
-      this.link = new URL(text);
+      this.link = (URI.create(text)).toURL();
     } catch (MalformedURLException e) {
       throw new LukeException(e.getMessage(), e);
     }

lucene/queryparser/src/test/org/apache/lucene/queryparser/flexible/messages/TestNLS.java

@@ -68,7 +68,7 @@ public class TestNLS extends LuceneTestCase {
   }
 
   public void testNLSLoading_xx_XX() {
-    Locale locale = new Locale("xx", "XX", "");
+    Locale locale = Locale.of("xx", "XX", "");
     String message =
         NLS.getLocalizedMessage(
             MessagesTestBundle.Q0004E_INVALID_SYNTAX_ESCAPE_UNICODE_TRUNCATION, locale);