added test case to reproduce the issue

Author: chernser

jdbc-v2/src/test/java/com/clickhouse/jdbc/DataTypeTests.java

@@ -10,6 +10,7 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.testng.annotations.BeforeClass;
+import org.testng.annotations.DataProvider;
 import org.testng.annotations.Test;
 
 import java.math.BigDecimal;
@@ -1960,4 +1961,48 @@ public void testGeoMultiPolygon() throws Exception {
         }
     }
 
+    @Test(groups = { "integration" }, dataProvider = "testJSONReadDP")
+    public void testJSONRead(String json) throws Exception {
+        if (ClickHouseVersion.of(getServerVersion()).check("(,24.8]")) {
+            return; // JSON was introduced in 24.10
+        }
+        Properties createProperties = new Properties();
+        createProperties.put(ClientConfigProperties.serverSetting("allow_experimental_json_type"), "1");
+        runQuery("DROP TABLE IF EXISTS test_jdbc_json_read");
+        runQuery("CREATE TABLE test_jdbc_json_read (data JSON) ENGINE = MergeTree ORDER BY ()", createProperties);
+
+        try (Connection conn = getJdbcConnection(); Statement stmt = conn.createStatement()) {
+            final String sql = "INSERT INTO test_jdbc_json_read (data) VALUES ('%s'), ('{}')";
+            stmt.executeUpdate(String.format(sql, json));
+
+            try (ResultSet rs = stmt.executeQuery("SELECT * FROM test_jdbc_json_read")) {
+
+                assertTrue(rs.next());
+                Object jsonObj = rs.getObject(1);
+                assertTrue(rs.next());
+                Object emptyJsonObj = rs.getObject(1);
+                assertFalse(rs.next());
+            }
+        }
+    }
+
+    @DataProvider(name = "testJSONReadDP")
+    public Object[][] testJSONReadDP() {
+        return new Object[][] {
+                {"{\"key\": \"value\"}"}, // Simple object
+                {"{\"numbers\":[1, 2, 3]}"},
+                {"{\"strings\":[\"one\", \"two\", \"three\"]}"},
+                {"{\"nested\":{\"key\": \"value\"}}"}, // nested objects
+                {"{\"nested\":{\"numbers\":[1, 2, 3]}}"}, // nested objects
+                {"{\"nested\":{\"strings\":[\"one\", \"two\", \"three\"]}}"}, // nested objects
+                {"{\"array\":[{\"key\": \"value\"},{\"key\": \"value\"}]}"}, // array of objects
+                {"{\"array\":[{\"numbers\":[1, 2, 3]},{\"strings\":[\"one\", \"two\", \"three\"]}]}"}, // array of objects
+                {"{\"array\":[{\"nested\":{\"key\": \"value\"}},{\"nested\":{\"numbers\":[1, 2, 3]}}]}"}, // array of objects
+                {"{\"array\":[{\"nested\":{\"strings\":[\"one\", \"two\", \"three\"]}}]}"}, // array of objects
+                {"{\"array\":[{\"nested\":[{\"key\": \"value\"}]}]}"}, // simple array of objects
+                {"{\"level1\": {\"level2\": {\"level3\": \"value\"}}}"}, // deep nested objects
+                {"{\"level1\": {\"level2\": {\"level3\": {\"level4\": \"value\"}}}}"}, // deep nested objects
+
+        };
+    }
 }