genericjdbcdao.java

spring+acegi编写的网上书城

package net.livebookstore.dao.jdbc;

import java.io.Serializable;

import org.springframework.jdbc.core.support.JdbcDaoSupport;

/**
 * Jdbc implementation of GenericDao.
 * 
 * @author Xuefeng
 * 
 * @deprecated
 */
public class GenericJdbcDao<T> extends JdbcDaoSupport {

    private final DomainRowMapper mapper;
    private final Class<T> clazz;
    private final String columnList;
    private final String parameterList;

    public GenericJdbcDao(Class<T> clazz) {
        this.clazz = clazz;
        this.mapper = new DomainRowMapper(clazz);
        StringBuffer columns = new StringBuffer();
        StringBuffer parameters = new StringBuffer();
        for(String c : mapper.getColumns()) {
            columns.append(',').append(c);
            parameters.append(",?");
        }
        columnList = columns.substring(1);
        parameterList = parameters.substring(1);
    }

    public void create(T t) {
        Object[] values = new Object[mapper.getColumns().length];
        int n = 0;
        for(String c : mapper.getColumns()) {
            values[n] = mapper.getValue(t, c);
            n++;
        }
        getJdbcTemplate().update(
                "insert into " + mapper.getTable() + "(" + columnList + ") values (" + parameterList + ")",
                values
        );
    }

    public void delete(T t) {
        getJdbcTemplate().update(
                "delete from " + mapper.getTable() + " where " + mapper.getId() + "=?",
                new Object[] { mapper.getValue(t, mapper.getId()) }
        );
    }

    public Object query(Serializable id) {
        return getJdbcTemplate().queryForObject(
                "select " + columnList + " from " + mapper.getTable() + " where " + mapper.getId() + "=?",
                new Object[] { id },
                mapper
        );
    }

    public void update(T t) {
        StringBuffer updateSql = new StringBuffer();
        updateSql.append("update ")
                 .append(mapper.getTable())
                 .append(" set ");
        String[] columns = mapper.getColumns();
        for(int i=1; i<columns.length; i++) {
            updateSql.append(columns[i]).append("=?,");
        }
        updateSql.deleteCharAt(updateSql.length()-1);
        updateSql.append(" where ").append(mapper.getId() + "=?");
        Object[] values = new Object[columns.length];
        for(int i=0; i<values.length-1; i++) {
            values[i] = mapper.getValue(t, columns[i+1]);
        }
        values[values.length-1] = mapper.getValue(t, mapper.getId());
        getJdbcTemplate().update(
                updateSql.toString(),
                new Object[] { mapper.getValue(t, mapper.getId()) }
        );
    }

}