articletree.java

连接数据库的一个JAVA BEAN,金审项目,ORACLE数据库

import java.sql.*;

public class ArticleTree {
	public static void main(String[] args) {
		new ArticleTree().show();
	}
	
	public void show() {
		Connection conn = null;
		Statement stmt = null;
		ResultSet rs = null;
		try {
			Class.forName("com.mysql.jdbc.Driver");

			conn = DriverManager
					.getConnection("jdbc:mysql://localhost/bbs?user=root&password=root");
			stmt = conn.createStatement();
			rs = stmt.executeQuery("select * from article where pid = 0"); 
			while(rs.next()){
				System.out.println(rs.getString("cont"));
				tree(conn, rs.getInt("id"), 1);
			}
		} catch(ClassNotFoundException e) {
			e.printStackTrace();
		} catch (SQLException e) {
			e.printStackTrace();
		} finally {
			try {
				if(rs != null) {
					rs.close();
					rs = null;
				}
				if(stmt != null) {
					stmt.close();
					stmt = null;
				}
				if(conn != null) {
					conn.close();
					conn = null;
				}
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
	}
	
	private void tree(Connection conn, int id, int level) {
		Statement stmt = null;
		ResultSet rs = null;
		
		StringBuffer strPre = new StringBuffer("");
		for(int i=0; i<level; i++) {
			strPre.append("    ");
		}
		
		try {
			stmt = conn.createStatement();
			String sql = "select * from article where pid = " + id;
			rs = stmt.executeQuery(sql);
			while(rs.next()) {
				System.out.println(strPre + rs.getString("cont"));
				if(rs.getInt("isleaf") != 0)
					tree(conn, rs.getInt("id"), level + 1);
			}
			
		} catch (SQLException e) {
			e.printStackTrace();
		} finally {
			try {
				if(rs != null) {
					rs.close();
					rs = null;
				}
				if(stmt != null) {
					stmt.close();
					stmt = null;
				}
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
	}
}