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 *   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.
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package org.apache.cayenne.dbsync.reverse.dbload;

import java.sql.DatabaseMetaData;
import java.sql.ResultSet;
import java.sql.SQLException;

import org.apache.cayenne.dba.DbAdapter;
import org.apache.cayenne.map.DbEntity;

public abstract class PerEntityLoader extends AbstractLoader {

    PerEntityLoader(DbAdapter adapter, DbLoaderConfiguration config, DbLoaderDelegate delegate) {
        super(adapter, config, delegate);
    }

    @Override
    public void load(DatabaseMetaData metaData, DbLoadDataStore map) throws SQLException {
        for(DbEntity dbEntity : map.getDbEntities()) {
            if(!shouldLoad(dbEntity)) {
                continue;
            }
            try(ResultSet rs = getResultSet(dbEntity, metaData)) {
                while(rs.next()) {
                    processResultSet(dbEntity, map, rs);
                }
            } catch (SQLException ex) {
                if(!catchException(dbEntity, ex)) {
                    throw ex;
                }
            }
        }
    }

    boolean shouldLoad(DbEntity entity) {
        return true;
    }

    boolean catchException(DbEntity entity, SQLException ex) {
        return false;
    }

    abstract ResultSet getResultSet(DbEntity dbEntity, DatabaseMetaData metaData) throws SQLException;

    abstract void processResultSet(DbEntity dbEntity, DbLoadDataStore map, ResultSet rs) throws SQLException;
}