topiccategoryserviceimpl.java

青年论坛设计想关代码

package com.ql.bbs.service.impl;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.List;

import com.ql.bbs.model.TopicCategory;
import com.ql.bbs.model.User;
import com.ql.bbs.service.TopicCategoryService;
import com.ql.bbs.util.JdbcUtils;

public class TopicCategoryServiceImpl implements TopicCategoryService {

	/**
	 * 增加类别
	 */
	public boolean addTopicCategory(TopicCategory category) {
		Connection con = null;
		PreparedStatement pstmt = null;
		ResultSet rs = null;
		
		//插入新的类别
		String sql1 = "insert into t_category(name ,description ,parentId,isLeaf,grade) "+
					 "values(?,?,?,?,?)";
		
		//查找父ID
		String sql2 = "select name from t_category where id = ?";
		
		//更新父类别的叶子标识
		String sql3 = "update t_category set isLeaf = 0 where id = ?";    
		try {
			con = JdbcUtils.getInstance().getConnection();
			//设置自动提交事务为F
			con.setAutoCommit(false); 
			//插入新的类别
			pstmt = con.prepareStatement(sql1);
			pstmt.setString(1, category.getName());
			pstmt.setString(2, category.getDescrption());
			pstmt.setInt(3, category.getPid());
			pstmt.setInt(4, 1);
			pstmt.setInt(5, category.getGrade());
			pstmt.executeUpdate();
			
			//查找父ID
			pstmt = con.prepareStatement(sql2);
			pstmt.setInt(1, category.getPid());
			rs = pstmt.executeQuery();
			if (rs.next()) {
				//更新父类别的叶子标识
				pstmt = con.prepareStatement(sql3);
				pstmt.setInt(1, category.getPid());
				pstmt.executeUpdate();
			}
			//提交事务
			con.commit();
			con.setAutoCommit(true);
		} catch (Exception e) {
			e.printStackTrace();
			return false;
		} finally {
			JdbcUtils.getInstance().close(con, pstmt, rs);
		}
		return true;
	}

	/**
	 * 删除类别
	 *  删除子类别的时候,父类别的isleaf是否要变----------->这点是否要完成???
	 */
	public boolean delTopicCategory(int id) {
		Connection con = null;
		PreparedStatement pstmt = null;
		ResultSet rs = null;
		String sql = "delete from t_category where id = ?";
		try {
			con = JdbcUtils.getInstance().getConnection();
			pstmt = con.prepareStatement(sql);
			pstmt.setInt(1, id);
			pstmt.executeUpdate();
		} catch (Exception e) {
			e.printStackTrace();
			return false;
		} finally {
			JdbcUtils.getInstance().close(con, pstmt, rs);
		}
		return true;
	}

	/**
	 * 查找类别
	 */
	public List findTopicCategories() {
		// TODO Auto-generated method stub
		return null;
	}

	/**
	 * 按ID查找类别
	 */
	public TopicCategory findTopicCategory(int id) {
		Connection con = null;
		PreparedStatement pstmt = null;
		ResultSet rs = null;
		TopicCategory topicCategory = null;
		String sql = "select name ,description ,parentId,isLeaf,grade " +
					 "from t_category where id=?";
		try {
			con = JdbcUtils.getInstance().getConnection();
			pstmt = con.prepareStatement(sql);
			pstmt.setInt(1, id);
			rs = pstmt.executeQuery();
			
			if (rs.next()) {
				topicCategory = new TopicCategory();
				topicCategory.setId(id);
				topicCategory.setName(rs.getString("name"));
				topicCategory.setDescrption(rs.getString("descrption"));
				topicCategory.setPid(rs.getInt("parentId"));
				topicCategory.setIsLeaf(rs.getInt("isLeaf"));
				topicCategory.setGrade(rs.getInt("grade"));
			}
			
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		} finally {
			JdbcUtils.getInstance().close(con, pstmt, rs);
		}
		return topicCategory;
	}

	/**
	 * 更新类别
	 */
	public boolean updateTopicCategory(TopicCategory category) {
		Connection con = null;
		PreparedStatement pstmt = null;
		ResultSet rs = null;
		String sql = "update t_category set name = ?, description = ? where id = ? " ;
		try {
			con = JdbcUtils.getInstance().getConnection();
			pstmt = con.prepareStatement(sql);
			
			pstmt.setString(1, category.getName());
			pstmt.setString(2, category.getDescrption());
			pstmt.setInt(3, category.getId());
			pstmt.executeUpdate();
		} catch (Exception e) {
			e.printStackTrace();
			return false;
		} finally {
			JdbcUtils.getInstance().close(con, pstmt, rs);
		}
		return true;
	}

}