refactor: support java 21, drop java 8

.github/workflows/java-publish.yml

@@ -194,11 +194,11 @@ jobs:
         with:
           ref: ${{ inputs.ref }}
       - uses: Swatinem/rust-cache@v2
-      - name: Set up Java 8
+      - name: Set up Java 11
         uses: actions/setup-java@v4
         with:
           distribution: corretto
-          java-version: 8
+          java-version: 11
           cache: "maven"
           server-id: ossrh
           server-username: SONATYPE_USER
@@ -228,7 +228,7 @@ jobs:
         working-directory: java
         run: |
           mvn --batch-mode -DskipTests -Drust.release.build=true package
-      - name: Publish with Java 8
+      - name: Publish with Java 11
         if: |
           github.event_name == 'release' ||
           inputs.mode == 'release'

.github/workflows/java.yml

@@ -51,7 +51,7 @@ jobs:
     timeout-minutes: 60
     strategy:
       matrix:
-        java-version: [8, 11, 17]
+        java-version: [11, 17, 21]
     name: Build and Test with Java ${{ matrix.java-version }}
     steps:
       - name: Checkout repository

java/AGENTS.md

@@ -10,4 +10,4 @@ lint rust: `cargo clippy --tests --manifest-path ./lance-jni/Cargo.toml`
 compile: `./mvnw compile`
 test: `./mvnw test`
 
-JDK: pom.xml targets Java 8 (`maven.compiler.release` 8); align Rust toolchain with repository `rust-toolchain.toml`.
+JDK: pom.xml targets Java 11 (`maven.compiler.release` 11); align Rust toolchain with repository `rust-toolchain.toml`.

java/pom.xml

@@ -28,11 +28,11 @@
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <arrow.version>15.0.0</arrow.version>
+        <arrow.version>18.3.0</arrow.version>
         <substrait.version>0.28.1</substrait.version>
         <spotless.skip>false</spotless.skip>
-        <spotless.version>2.30.0</spotless.version>
-        <spotless.java.googlejavaformat.version>1.7</spotless.java.googlejavaformat.version>
+        <spotless.version>2.43.0</spotless.version>
+        <spotless.java.googlejavaformat.version>1.22.0</spotless.java.googlejavaformat.version>
         <scala.version>2.12.19</scala.version>
         <scala.binary.version>2.12</scala.binary.version>
         <!-- Please also update .scalafmt.conf when you change it here -->
@@ -419,8 +419,8 @@
                 <jdk>[11,)</jdk>
             </activation>
             <properties>
-                <!-- Ping release target to JDK8 to link only against Java 8 APIs -->
-                <maven.compiler.release>8</maven.compiler.release>
+                <!-- Ping release target to JDK11 to link only against Java 11 APIs -->
+                <maven.compiler.release>11</maven.compiler.release>
             </properties>
             <build>
                 <plugins>

java/src/main/java/org/lance/Dataset.java

@@ -688,7 +688,9 @@ public List<Version> listVersions() {
 
   private native List<Version> nativeListVersions();
 
-  /** @return the latest version of the dataset. */
+  /**
+   * @return the latest version of the dataset.
+   */
   public long latestVersion() {
     try (LockManager.WriteLock writeLock = lockManager.acquireWriteLock()) {
       Preconditions.checkArgument(nativeDatasetHandle != 0, "Dataset is closed");
@@ -957,7 +959,9 @@ public Optional<Transaction> readTransaction() {
 
   private native Transaction nativeReadTransaction();
 
-  /** @return all the created indexes names */
+  /**
+   * @return all the created indexes names
+   */
   public List<String> listIndexes() {
     try (LockManager.ReadLock readLock = lockManager.acquireReadLock()) {
       Preconditions.checkArgument(nativeDatasetHandle != 0, "Dataset is closed");

java/src/main/java/org/lance/Fragment.java

@@ -124,7 +124,9 @@ public int getId() {
     return fragmentMetadata.getId();
   }
 
-  /** @return row counts in this Fragment */
+  /**
+   * @return row counts in this Fragment
+   */
   public int countRows() {
     return countRowsNative(dataset, fragmentMetadata.getId());
   }

java/src/test/java/org/lance/TestUtils.java

@@ -530,6 +530,7 @@ public List<FragmentMetadata> createNewFragment(int rowCount, int maxRowsPerFile
       }
       return fragmentMetas;
     }
+
     /**
      * Test method to update columns. Note that for simplicity, the updated column rowid is fixed
      * with [0, updateNum). Please only use this method to test the first fragment.
@@ -606,6 +607,7 @@ public static final class BlobTestDataset {
 
     /** Lance blob metadata key required by Rust. */
     private static final String BLOB_META_KEY = "lance-encoding:blob";
+
     /** Lance blob metadata value. */
     private static final String BLOB_META_TRUE = "true";