From fd61ddbd214f9e30c08fc47398e46410b339854a Mon Sep 17 00:00:00 2001
From: kimminseok <alstjr706@naver.com>
Date: Tue, 7 Oct 2025 14:15:10 +0900
Subject: [PATCH] feat(java): implement isBeforeFirst(), isAfterLast() in
 JDBC4ResultSet

---
 .../java/tech/turso/core/TursoResultSet.java  | 10 +++++
 .../java/tech/turso/jdbc4/JDBC4ResultSet.java |  4 +-
 .../tech/turso/jdbc4/JDBC4ResultSetTest.java  | 44 +++++++++++++++++++
 3 files changed, 56 insertions(+), 2 deletions(-)

diff --git a/bindings/java/src/main/java/tech/turso/core/TursoResultSet.java b/bindings/java/src/main/java/tech/turso/core/TursoResultSet.java
index fe9d72067..e880ae6b4 100644
--- a/bindings/java/src/main/java/tech/turso/core/TursoResultSet.java
+++ b/bindings/java/src/main/java/tech/turso/core/TursoResultSet.java
@@ -99,6 +99,16 @@ public final class TursoResultSet {
     return lastStepResult != null && lastStepResult.isRow();
   }
 
+  /** Checks whether the cursor is positioned after the last row. */
+  public boolean isPastLastRow() {
+    return pastLastRow;
+  }
+
+  /** Gets the current row number (0-based, 0 means before first row). */
+  public int getRow() {
+    return row;
+  }
+
   /**
    * Checks the status of the result set.
    *
diff --git a/bindings/java/src/main/java/tech/turso/jdbc4/JDBC4ResultSet.java b/bindings/java/src/main/java/tech/turso/jdbc4/JDBC4ResultSet.java
index 471351073..a094abe37 100644
--- a/bindings/java/src/main/java/tech/turso/jdbc4/JDBC4ResultSet.java
+++ b/bindings/java/src/main/java/tech/turso/jdbc4/JDBC4ResultSet.java
@@ -413,12 +413,12 @@ public final class JDBC4ResultSet implements ResultSet, ResultSetMetaData {
 
   @Override
   public boolean isBeforeFirst() throws SQLException {
-    throw new UnsupportedOperationException("not implemented");
+    return resultSet.isOpen() && resultSet.getRow() == 0 && !resultSet.isPastLastRow();
   }
 
   @Override
   public boolean isAfterLast() throws SQLException {
-    throw new UnsupportedOperationException("not implemented");
+    return resultSet.isOpen() && resultSet.isPastLastRow();
   }
 
   @Override
diff --git a/bindings/java/src/test/java/tech/turso/jdbc4/JDBC4ResultSetTest.java b/bindings/java/src/test/java/tech/turso/jdbc4/JDBC4ResultSetTest.java
index 1e4ab80f1..1d634ada7 100644
--- a/bindings/java/src/test/java/tech/turso/jdbc4/JDBC4ResultSetTest.java
+++ b/bindings/java/src/test/java/tech/turso/jdbc4/JDBC4ResultSetTest.java
@@ -642,4 +642,48 @@ class JDBC4ResultSetTest {
 
     assertEquals(BigDecimal.valueOf(12345.67), resultSet.getBigDecimal("amount"));
   }
+
+  @Test
+  void test_isBeforeFirst_and_isAfterLast() throws Exception {
+    stmt.executeUpdate("CREATE TABLE test_position (id INTEGER);");
+    stmt.executeUpdate("INSERT INTO test_position VALUES (1);");
+    stmt.executeUpdate("INSERT INTO test_position VALUES (2);");
+
+    ResultSet resultSet = stmt.executeQuery("SELECT * FROM test_position");
+
+    // Before first row
+    assertTrue(resultSet.isBeforeFirst());
+    assertFalse(resultSet.isAfterLast());
+
+    // First row
+    resultSet.next();
+    assertFalse(resultSet.isBeforeFirst());
+    assertFalse(resultSet.isAfterLast());
+
+    // Second row
+    resultSet.next();
+    assertFalse(resultSet.isBeforeFirst());
+    assertFalse(resultSet.isAfterLast());
+
+    // After last row
+    resultSet.next();
+    assertFalse(resultSet.isBeforeFirst());
+    assertTrue(resultSet.isAfterLast());
+  }
+
+  @Test
+  void test_isBeforeFirst_with_empty_resultSet() throws Exception {
+    stmt.executeUpdate("CREATE TABLE test_empty (id INTEGER);");
+
+    ResultSet resultSet = stmt.executeQuery("SELECT * FROM test_empty");
+
+    // Before calling next()
+    assertTrue(resultSet.isBeforeFirst());
+    assertFalse(resultSet.isAfterLast());
+
+    // After calling next() on empty ResultSet
+    assertFalse(resultSet.next());
+    assertFalse(resultSet.isBeforeFirst());
+    assertTrue(resultSet.isAfterLast());
+  }
 }