Add SeaTunnelDataSourceClient docs (#5)

* Add guava dependency

* Add client doc
diff --git a/datasource-client/src/main/java/org/apache/seatunnel/datasource/client/SeaTunnelDataSourceClient.java b/datasource-client/src/main/java/org/apache/seatunnel/datasource/client/SeaTunnelDataSourceClient.java
index 46dd654..6346ff4 100644
--- a/datasource-client/src/main/java/org/apache/seatunnel/datasource/client/SeaTunnelDataSourceClient.java
+++ b/datasource-client/src/main/java/org/apache/seatunnel/datasource/client/SeaTunnelDataSourceClient.java
@@ -34,46 +34,6 @@
     }
 
     @Override
-    public List<DataSourcePluginInfo> listAllDataSources() {
-        return null;
-    }
-
-    @Override
-    public OptionRule queryDataSourceFieldByName(String dataSourceName) {
-        return null;
-    }
-
-    @Override
-    public Boolean checkDataSourceFields(Map<String, Object> parameters) {
-        return null;
-    }
-
-    @Override
-    public DataSource queryDataSourceById(Long dataSourceId) {
-        return null;
-    }
-
-    @Override
-    public Boolean saveDataSource(String dataSourceName, String comment, String pluginName, Map<String, Object> parameters) {
-        return false;
-    }
-
-    @Override
-    public Boolean deleteDataSource(Long id) {
-        return false;
-    }
-
-    @Override
-    public Boolean updateDataSource(Long dataSourceId, String dataSourceName, String comment, Map<String, Object> parameters) {
-        return false;
-    }
-
-    @Override
-    public Boolean checkDataSourceConnectivity(Map<String, Object> dataSourceParams) {
-        return null;
-    }
-
-    @Override
     public OptionRule getDataSourceMetadataFieldsByDataSourceName(String dataSourceName) {
         return null;
     }
@@ -99,6 +59,46 @@
     }
 
     @Override
+    public List<DataSourcePluginInfo> listAllDataSources() {
+        return null;
+    }
+
+    @Override
+    public OptionRule queryDataSourceFieldByName(String pluginName) {
+        return null;
+    }
+
+    @Override
+    public Boolean checkDataSourceFields(String pluginName, Map<String, Object> parameters) {
+        return null;
+    }
+
+    @Override
+    public DataSource queryDataSourceById(Long dataSourceId) {
+        return null;
+    }
+
+    @Override
+    public Boolean saveDataSource(String dataSourceName, String comment, String pluginName, Map<String, Object> parameters) {
+        return null;
+    }
+
+    @Override
+    public Boolean deleteDataSource(Long id) {
+        return null;
+    }
+
+    @Override
+    public Boolean updateDataSource(Long dataSourceId, String dataSourceName, String comment, Map<String, Object> parameters) {
+        return null;
+    }
+
+    @Override
+    public Boolean checkDataSourceConnectivity(String pluginName, Map<String, Object> dataSourceParams) {
+        return null;
+    }
+
+    @Override
     public Boolean createTable(Long datasourceId, String databaseName, String tableName, Map<String, String> tableFields, String description) {
         return null;
     }
diff --git a/datasource-client/src/main/java/org/apache/seatunnel/datasource/client/SimpleSeaTunnelDataSourceClient.java b/datasource-client/src/main/java/org/apache/seatunnel/datasource/client/SimpleSeaTunnelDataSourceClient.java
index 6e1689f..dafa783 100644
--- a/datasource-client/src/main/java/org/apache/seatunnel/datasource/client/SimpleSeaTunnelDataSourceClient.java
+++ b/datasource-client/src/main/java/org/apache/seatunnel/datasource/client/SimpleSeaTunnelDataSourceClient.java
@@ -39,12 +39,12 @@
     }
 
     @Override
-    public OptionRule queryDataSourceFieldByName(String dataSourceName) {
+    public OptionRule queryDataSourceFieldByName(String pluginName) {
         return null;
     }
 
     @Override
-    public Boolean checkDataSourceFields(Map<String, Object> parameters) {
+    public Boolean checkDataSourceFields(String pluginName, Map<String, Object> parameters) {
         return null;
     }
 
@@ -55,21 +55,21 @@
 
     @Override
     public Boolean saveDataSource(String dataSourceName, String comment, String pluginName, Map<String, Object> parameters) {
-        return false;
+        return null;
     }
 
     @Override
     public Boolean deleteDataSource(Long id) {
-        return false;
+        return null;
     }
 
     @Override
     public Boolean updateDataSource(Long dataSourceId, String dataSourceName, String comment, Map<String, Object> parameters) {
-        return false;
+        return null;
     }
 
     @Override
-    public Boolean checkDataSourceConnectivity(Map<String, Object> dataSourceParams) {
+    public Boolean checkDataSourceConnectivity(String pluginName, Map<String, Object> dataSourceParams) {
         return null;
     }
 }
diff --git a/datasource-client/src/main/java/org/apache/seatunnel/datasource/service/SeaTunnelDataSourceService.java b/datasource-client/src/main/java/org/apache/seatunnel/datasource/service/SeaTunnelDataSourceService.java
index 9b2db50..d383c63 100644
--- a/datasource-client/src/main/java/org/apache/seatunnel/datasource/service/SeaTunnelDataSourceService.java
+++ b/datasource-client/src/main/java/org/apache/seatunnel/datasource/service/SeaTunnelDataSourceService.java
@@ -26,19 +26,76 @@
 
 public interface SeaTunnelDataSourceService {
 
+    /**
+     * get all data source plugins
+     *
+     * @return data source plugins info
+     */
     List<DataSourcePluginInfo> listAllDataSources();
 
-    OptionRule queryDataSourceFieldByName(String dataSourceName);
+    /**
+     * get data source plugin fields
+     *
+     * @param pluginName data source name
+     * @return data source plugin fields
+     */
+    OptionRule queryDataSourceFieldByName(String pluginName);
 
-    Boolean checkDataSourceFields(Map<String, Object> parameters);
+    /**
+     * check data source params is valid and connectable
+     *
+     * @param parameters data source params
+     *                   eg mysql plugin
+     *                   key: url // jdbc url
+     *                   key: username
+     *                   key: password
+     *                   other key...
+     * @return true if valid, false if invalid
+     */
+    Boolean checkDataSourceFields(String pluginName, Map<String, Object> parameters);
 
     DataSource queryDataSourceById(Long dataSourceId);
 
+    /**
+     * save data source
+     *
+     * @param dataSourceName data source name
+     * @param comment        data source comment
+     * @param pluginName     data source plugin name
+     * @param parameters     data source params
+     *                       eg mysql plugin
+     *                       key: url // jdbc url
+     *                       key: username
+     *                       key: password
+     *                       other key...
+     * @return save result
+     */
     Boolean saveDataSource(String dataSourceName, String comment, String pluginName, Map<String, Object> parameters);
 
+    /**
+     * delete data source, only set delete flag, we don't really delete data.
+     *
+     * @param id data source id
+     * @return delete result
+     */
     Boolean deleteDataSource(Long id);
 
+    /**
+     * update data source
+     *
+     * @param dataSourceId   data source id
+     * @param dataSourceName data source name
+     * @param comment        data source comment
+     * @param parameters     data source params
+     * @return update result
+     */
     Boolean updateDataSource(Long dataSourceId, String dataSourceName, String comment, Map<String, Object> parameters);
 
-    Boolean checkDataSourceConnectivity(Map<String, Object> dataSourceParams);
+    /**
+     * we can use this method to check data source connectivity
+     *
+     * @param dataSourceParams data source params
+     * @return check result
+     */
+    Boolean checkDataSourceConnectivity(String pluginName, Map<String, Object> dataSourceParams);
 }