feat: add LanceNamespaceCatalog backed by Lance namespace API

lance-flink-1.18/pom.xml

@@ -26,6 +26,18 @@
             <artifactId>lance-core</artifactId>
         </dependency>
 
+        <!-- Lance Namespace：可插拔 Catalog 后端契约，及 OpenAPI 生成的
+             模型类（DescribeTableResponse / CreateTableRequest 等） -->
+        <dependency>
+            <groupId>org.lance</groupId>
+            <artifactId>lance-namespace-core</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>org.lance</groupId>
+            <artifactId>lance-namespace-apache-client</artifactId>
+        </dependency>
+
         <!-- Arrow -->
         <dependency>
             <groupId>org.apache.arrow</groupId>

lance-flink-1.19/pom.xml

@@ -26,6 +26,18 @@
             <artifactId>lance-core</artifactId>
         </dependency>
 
+        <!-- Lance Namespace：可插拔 Catalog 后端契约，及 OpenAPI 生成的
+             模型类（DescribeTableResponse / CreateTableRequest 等） -->
+        <dependency>
+            <groupId>org.lance</groupId>
+            <artifactId>lance-namespace-core</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>org.lance</groupId>
+            <artifactId>lance-namespace-apache-client</artifactId>
+        </dependency>
+
         <!-- Arrow -->
         <dependency>
             <groupId>org.apache.arrow</groupId>

lance-flink-1.20/pom.xml

@@ -26,6 +26,18 @@
             <artifactId>lance-core</artifactId>
         </dependency>
 
+        <!-- Lance Namespace：可插拔 Catalog 后端契约，及 OpenAPI 生成的
+             模型类（DescribeTableResponse / CreateTableRequest 等） -->
+        <dependency>
+            <groupId>org.lance</groupId>
+            <artifactId>lance-namespace-core</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>org.lance</groupId>
+            <artifactId>lance-namespace-apache-client</artifactId>
+        </dependency>
+
         <!-- Arrow -->
         <dependency>
             <groupId>org.apache.arrow</groupId>

pom.xml

@@ -58,9 +58,38 @@
                         <groupId>org.slf4j</groupId>
                         <artifactId>slf4j-api</artifactId>
                     </exclusion>
+                    <exclusion>
+                        <groupId>org.apache.arrow</groupId>
+                        <artifactId>arrow-memory-core</artifactId>
+                    </exclusion>
                 </exclusions>
             </dependency>
 
+            <!-- Explicitly manage arrow-memory-core to align with arrow-memory-netty version -->
+            <dependency>
+                <groupId>org.apache.arrow</groupId>
+                <artifactId>arrow-memory-core</artifactId>
+                <version>${arrow.version}</version>
+            </dependency>
+
+            <!-- ==================== Lance Namespace（可插拔 Catalog 后端契约）==================== -->
+            <!-- LanceNamespace 接口与插件注册表，所有 catalog 操作通过此接口路由到具体实现
+                 （dir / rest / glue / hive2 / unity 等）。详见：
+                 https://github.com/lancedb/lance-namespace -->
+            <dependency>
+                <groupId>org.lance</groupId>
+                <artifactId>lance-namespace-core</artifactId>
+                <version>${lance-namespace.version}</version>
+            </dependency>
+
+            <!-- OpenAPI 生成的 Apache HTTP 客户端，提供 Request/Response 模型类
+                 （DescribeTableResponse / CreateTableRequest 等），以及 RestNamespace 实现 -->
+            <dependency>
+                <groupId>org.lance</groupId>
+                <artifactId>lance-namespace-apache-client</artifactId>
+                <version>${lance-namespace.version}</version>
+            </dependency>
+
             <!-- ==================== Apache Arrow ==================== -->
             <dependency>
                 <groupId>org.apache.arrow</groupId>

src/main/java/org/apache/flink/connector/lance/catalog/namespace/LanceNamespaceConfig.java

@@ -0,0 +1,213 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.connector.lance.catalog.namespace;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Optional;
+
+/**
+ * Configuration for Lance Namespace integration.
+ *
+ * <p>Supports:
+ * <ul>
+ *   <li>Namespace implementation selection ({@code dir}, {@code rest}, custom)</li>
+ *   <li>Implementation-specific parameters (root path, REST URI)</li>
+ *   <li>Extra level configuration (for Spark compatibility)</li>
+ *   <li>Parent prefix support (for Hive 3 compatibility)</li>
+ * </ul>
+ */
+public class LanceNamespaceConfig {
+
+    // Configuration keys
+    public static final String KEY_IMPL = "impl";
+    public static final String KEY_ROOT = "root";
+    public static final String KEY_URI = "uri";
+    public static final String KEY_EXTRA_LEVEL = "extra_level";
+    public static final String KEY_PARENT = "parent";
+    public static final String KEY_PARENT_DELIMITER = "parent_delimiter";
+
+    private final String impl;
+    private final Map<String, String> properties;
+    private final Optional<String> extraLevel;
+    private final Optional<String> parent;
+    private final String parentDelimiter;
+
+    /**
+     * Create configuration from properties map.
+     */
+    public static LanceNamespaceConfig from(Map<String, String> properties) {
+        return new LanceNamespaceConfig(properties);
+    }
+
+    /**
+     * Create builder for configuration.
+     */
+    public static Builder builder() {
+        return new Builder();
+    }
+
+    private LanceNamespaceConfig(Map<String, String> properties) {
+        this.properties = new HashMap<>(Objects.requireNonNull(properties, "Properties cannot be null"));
+
+        // Extract required impl
+        this.impl = properties.get(KEY_IMPL);
+        if (this.impl == null || this.impl.isEmpty()) {
+            throw new IllegalArgumentException("Missing required configuration: " + KEY_IMPL);
+        }
+
+        // Extract optional extra level
+        String extraLevelValue = properties.get(KEY_EXTRA_LEVEL);
+        this.extraLevel = extraLevelValue != null && !extraLevelValue.isEmpty()
+                ? Optional.of(extraLevelValue) : Optional.empty();
+
+        // Extract optional parent prefix
+        String parentValue = properties.get(KEY_PARENT);
+        this.parent = parentValue != null && !parentValue.isEmpty()
+                ? Optional.of(parentValue) : Optional.empty();
+
+        // Extract parent delimiter
+        this.parentDelimiter = properties.getOrDefault(KEY_PARENT_DELIMITER, ".");
+    }
+
+    /**
+     * Get namespace implementation type.
+     */
+    public String getImpl() {
+        return impl;
+    }
+
+    /**
+     * Get all configuration properties.
+     */
+    public Map<String, String> getProperties() {
+        return Collections.unmodifiableMap(properties);
+    }
+
+    /**
+     * Get root path for directory namespace implementation.
+     */
+    public Optional<String> getRoot() {
+        return Optional.ofNullable(properties.get(KEY_ROOT));
+    }
+
+    /**
+     * Get URI for REST namespace implementation.
+     */
+    public Optional<String> getUri() {
+        return Optional.ofNullable(properties.get(KEY_URI));
+    }
+
+    /**
+     * Get extra level configuration (for Spark compatibility).
+     */
+    public Optional<String> getExtraLevel() {
+        return extraLevel;
+    }
+
+    /**
+     * Get parent prefix configuration (for Hive 3 compatibility).
+     */
+    public Optional<String> getParent() {
+        return parent;
+    }
+
+    /**
+     * Get parent delimiter.
+     */
+    public String getParentDelimiter() {
+        return parentDelimiter;
+    }
+
+    /**
+     * Check if directory namespace implementation.
+     */
+    public boolean isDirectoryNamespace() {
+        return "dir".equals(impl);
+    }
+
+    /**
+     * Check if REST namespace implementation.
+     */
+    public boolean isRestNamespace() {
+        return "rest".equals(impl);
+    }
+
+    @Override
+    public String toString() {
+        return "LanceNamespaceConfig{"
+                + "impl='" + impl + '\''
+                + ", extraLevel=" + extraLevel
+                + ", parent=" + parent
+                + '}';
+    }
+
+    /**
+     * Builder for LanceNamespaceConfig.
+     */
+    public static class Builder {
+        private final Map<String, String> properties = new HashMap<>();
+
+        public Builder impl(String impl) {
+            properties.put(KEY_IMPL, impl);
+            return this;
+        }
+
+        public Builder root(String root) {
+            properties.put(KEY_ROOT, root);
+            return this;
+        }
+
+        public Builder uri(String uri) {
+            properties.put(KEY_URI, uri);
+            return this;
+        }
+
+        public Builder extraLevel(String extraLevel) {
+            properties.put(KEY_EXTRA_LEVEL, extraLevel);
+            return this;
+        }
+
+        public Builder parent(String parent) {
+            properties.put(KEY_PARENT, parent);
+            return this;
+        }
+
+        public Builder parentDelimiter(String delimiter) {
+            properties.put(KEY_PARENT_DELIMITER, delimiter);
+            return this;
+        }
+
+        public Builder property(String key, String value) {
+            properties.put(key, value);
+            return this;
+        }
+
+        public Builder properties(Map<String, String> props) {
+            properties.putAll(props);
+            return this;
+        }
+
+        public LanceNamespaceConfig build() {
+            return new LanceNamespaceConfig(properties);
+        }
+    }
+}