com.simple.orm.dao.impl.EntityRowMapper Maven / Gradle / Ivy

Go to download
package com.simple.orm.dao.impl;

import java.lang.reflect.Field;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.Map;

import javax.persistence.Column;

import org.springframework.jdbc.core.RowMapper;

public final class EntityRowMapper implements RowMapper {

	private Class entityClass=null;
	
	private Field[] fields= {};
	
	@SuppressWarnings("unchecked")
	public EntityRowMapper(Class entityClass, Field[] fields) {
		this.entityClass = (Class) entityClass;
		this.fields = fields;
	}

	public M mapRow(ResultSet rs, int rowNum) throws SQLException {
		M m = null;
		try {
			ResultSetMetaData rsmd = rs.getMetaData();
			int count = rsmd.getColumnCount();
			Map columnMap=new HashMap();
			for (int i = 1; i <=count; i++) {
				String columnName=rsmd.getColumnLabel(i);
				columnMap.put(columnName, i);
			}
			m = entityClass.newInstance();
			for (Field field : fields) {
				Column column = field.getAnnotation(Column.class);
				int columnIndex=columnMap.get(column.name());
				if(columnIndex<=0) {
					continue;
				}
				Object value = rs.getObject(columnIndex);
				field.setAccessible(true);
				field.set(m, value);
			}
		} catch (InstantiationException e) {
			e.printStackTrace();
		} catch (IllegalAccessException e) {
			e.printStackTrace();
		} catch (SecurityException e) {
			e.printStackTrace();
		} catch (IllegalArgumentException e) {
			e.printStackTrace();
		}
		return m;
	}
}