feat: add light java sdk (#3642)

* feat: add light java sdk

* test: add test

* refact: type

* fix: fix light

* fix: fix compile

* test: fix online mode

* fix: fix comment

---------

Co-authored-by: denglong <[email protected]>
Co-authored-by: 4paradigm <[email protected]>

Author: 3 people

java/openmldb-jdbc/src/main/java/com/_4paradigm/openmldb/sdk/SdkOption.java

@@ -45,6 +45,7 @@ public class SdkOption {
     private int glogLevel = 0;
     private String glogDir = "";
     private int maxSqlCacheSize = 50;
+    private boolean isLight = false;
 
     private void buildBaseOptions(BasicRouterOptions opt) {
         opt.setEnable_debug(getEnableDebug());

java/openmldb-jdbc/src/main/java/com/_4paradigm/openmldb/sdk/SqlException.java

@@ -20,4 +20,12 @@ public class SqlException extends Exception {
     public SqlException(String message) {
         super(message);
     }
+
+    public SqlException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public SqlException(Throwable cause) {
+        super(cause);
+    }
 }

java/openmldb-jdbc/src/main/java/com/_4paradigm/openmldb/sdk/impl/SqlClusterExecutor.java

@@ -62,27 +62,28 @@ public class SqlClusterExecutor implements SqlExecutor {
     private static final AtomicBoolean initialized = new AtomicBoolean(false);
     private SQLRouter sqlRouter;
     private DeploymentManager deploymentManager;
-    private ZKClient zkClient;
     private InsertPreparedStatementCache insertCache;
 
     public SqlClusterExecutor(SdkOption option, String libraryPath) throws SqlException {
         initJavaSdkLibrary(libraryPath);
-
+        ZKClient zkClient = null;
         if (option.isClusterMode()) {
             SQLRouterOptions sqlOpt = option.buildSQLRouterOptions();
             this.sqlRouter = sql_router_sdk.NewClusterSQLRouter(sqlOpt);
             sqlOpt.delete();
-            zkClient = new ZKClient(ZKConfig.builder()
-                    .cluster(option.getZkCluster())
-                    .namespace(option.getZkPath())
-                    .sessionTimeout((int)option.getSessionTimeout())
-                    .build());
-            try {
-                if (!zkClient.connect()) {
-                    throw new SqlException("zk client connect failed.");
+            if (!option.isLight()) {
+                zkClient = new ZKClient(ZKConfig.builder()
+                        .cluster(option.getZkCluster())
+                        .namespace(option.getZkPath())
+                        .sessionTimeout((int)option.getSessionTimeout())
+                        .build());
+                try {
+                    if (!zkClient.connect()) {
+                        throw new SqlException("zk client connect failed.");
+                    }
+                } catch (Exception e) {
+                    throw new SqlException("init zk client failed", e);
                 }
-            } catch (Exception e) {
-                throw new SqlException("init zk client failed. " + e.getMessage());
             }
         } else {
             StandaloneOptions sqlOpt = option.buildStandaloneOptions();

java/openmldb-jdbc/src/test/java/com/_4paradigm/openmldb/jdbc/SQLRouterSmokeTest.java

@@ -45,6 +45,7 @@
 
 public class SQLRouterSmokeTest {
     public static SqlExecutor clusterExecutor;
+    public static SqlExecutor lightClusterExecutor;
     public static SqlExecutor standaloneExecutor;
 
     static {
@@ -54,9 +55,10 @@ public class SQLRouterSmokeTest {
             option.setZkCluster(TestConfig.ZK_CLUSTER);
             option.setSessionTimeout(200000);
             clusterExecutor = new SqlClusterExecutor(option);
-            java.sql.Statement state = clusterExecutor.getStatement();
-            state.execute("SET @@execute_mode='online';");
-            state.close();
+            setOnlineMode(clusterExecutor);
+            option.setLight(true);
+            lightClusterExecutor = new SqlClusterExecutor(option);
+            setOnlineMode(lightClusterExecutor);
             // create standalone router
             SdkOption standaloneOption = new SdkOption();
             standaloneOption.setHost(TestConfig.HOST);
@@ -69,6 +71,16 @@ public class SQLRouterSmokeTest {
         }
     }
 
+    static void setOnlineMode(SqlExecutor executor) {
+        java.sql.Statement state = executor.getStatement();
+        try {
+            state.execute("SET @@execute_mode='online';");
+            state.close();
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+
     @Test
     void testMoreOptions() throws Exception {
         SdkOption option = new SdkOption();
@@ -82,7 +94,7 @@ void testMoreOptions() throws Exception {
 
     @DataProvider(name = "executor")
     public Object[] executor() {
-        return new Object[] { clusterExecutor, standaloneExecutor };
+        return new Object[] { clusterExecutor, lightClusterExecutor, standaloneExecutor };
     }
 
     @Test(dataProvider = "executor")
@@ -128,7 +140,7 @@ public void testSmoke(SqlExecutor router) {
 
             // select
             String select1 = "select * from tsql1010;";
-            SQLResultSet rs1 = (SQLResultSet) router .executeSQL(dbname, select1);
+            SQLResultSet rs1 = (SQLResultSet) router.executeSQL(dbname, select1);
 
             Assert.assertEquals(2, rs1.GetInternalSchema().getColumnList().size());
             Assert.assertEquals(Types.BIGINT, rs1.GetInternalSchema().getColumnType(0));

java/openmldb-spark-connector/src/main/java/com/_4paradigm/openmldb/spark/OpenmldbSource.java

@@ -53,6 +53,7 @@ public StructType inferSchema(CaseInsensitiveStringMap options) {
         option = new SdkOption();
         option.setZkCluster(zkCluster);
         option.setZkPath(zkPath);
+        option.setLight(true);
         String timeout = options.get("sessionTimeout");
         if (timeout != null) {
             option.setSessionTimeout(Integer.parseInt(timeout));

java/openmldb-spark-connector/src/main/java/com/_4paradigm/openmldb/spark/write/OpenmldbDataSingleWriter.java

@@ -44,6 +44,7 @@ public OpenmldbDataSingleWriter(OpenmldbWriteConfig config, int partitionId, lon
             SdkOption option = new SdkOption();
             option.setZkCluster(config.zkCluster);
             option.setZkPath(config.zkPath);
+            option.setLight(true);
             SqlClusterExecutor executor = new SqlClusterExecutor(option);
             String dbName = config.dbName;
             String tableName = config.tableName;

java/openmldb-spark-connector/src/main/java/com/_4paradigm/openmldb/spark/write/OpenmldbDataWriter.java

@@ -44,6 +44,7 @@ public OpenmldbDataWriter(OpenmldbWriteConfig config, int partitionId, long task
             SdkOption option = new SdkOption();
             option.setZkCluster(config.zkCluster);
             option.setZkPath(config.zkPath);
+            option.setLight(true);
             SqlClusterExecutor executor = new SqlClusterExecutor(option);
             String dbName = config.dbName;
             String tableName = config.tableName;

java/openmldb-spark-connector/src/main/scala/com/_4paradigm/openmldb/spark/read/OpenmldbPartitionReader.scala

@@ -13,6 +13,7 @@ class OpenmldbPartitionReader(config: OpenmldbReadConfig) extends PartitionReade
   val option = new SdkOption
   option.setZkCluster(config.zkCluster)
   option.setZkPath(config.zkPath)
+  option.setLight(true)
   val executor = new SqlClusterExecutor(option)
   val dbName: String = config.dbName
   val tableName: String = config.tableName