oracle生成表设计文档

package com.lagou.test;

import com.lowagie.text.*;
import com.lowagie.text.rtf.RtfWriter2;

import java.awt.*;
import java.io.FileOutputStream;
import java.sql.*;
import java.util.List;
import java.util.*;
/**
 * 数据库文档生成器 Oracle版
 * itext-2.1.7.jar
 * itext-rtf-2.1.7.jar
 */
public class GenerateTableDoc {
   
   
    //键类型字典
    private static Map<String,String> keyType = new HashMap<String,String>();
    //需要导出的目标表
    private static List<String> targetTable = new ArrayList<String>();
    static{
   
   
        //需要生成的表
        targetTable.add("TB_FEE_INFORMATION");
        targetTable.add("TB_LOAN_SCHEME");
        targetTable.add("TB_REGULATORY_REPORTING");
        targetTable.add("TB_BUSINESS_APPLY");

        targetTable.add("TB_BIZ_AMAPV_BBILLTX_DRAFT");
        targetTable.add("TB_BIZ_BANK_ACCEPTANCE_BILL");
        targetTable.add("TB_BIZ_AMAPV_BBILLTX_DTL");
        targetTable.add("TB_BILL_MSG");
        
    }
    //初始化jdbc
    static{
   
   
        try {
   
   
            keyType.put("P", "主键");
//			keyType.put("C", "Check");
            Class.forName("oracle.jdbc.OracleDriver");
        } catch (ClassNotFoundException e) {
   
   
            e.printStackTrace();
        }
    }
   
    private static String url = "jdbc:oracle:thin:@localhost:1521:orcl";//链接url
    private static String username = "root"; //用户名.需要设置默认表空间哈
    private static String password = "123456"; //密码
    private static String schema = "user"; //目标数据库名
    //查询所有表的sql语句
    private static String sql_get_all_tables = "select a.TABLE_NAME,b.COMMENTS from user_tables a,user_tab_comments b WHERE a.TABLE_NAME=b.TABLE_NAME order by TABLE_NAME";	//查询所有字段的sql语句
    private static String sql_get_all_columns = "select T1.column_name,T1.data_type,T1.data_length,t2.comments,T1.NULLABLE,(select max(constraint_type)    from user_constraints x left join user_cons_columns y on x.constraint_name=y.constraint_name where x.table_name=t1.TABLE_NAME and y.COLUMN_NAME=T1.column_name)  from user_tab_cols t1, user_col_comments t2, user_tab_comments t3  where t1.TABLE_NAME=t2.table_name(+)  and t1.COLUMN_NAME=t2.column_name(+)  and t1.TABLE_NAME=t3.table_name(+)  and t1.TABLE_NAME='{table_name}' order by T1.COLUMN_ID ";
    public static void main(String[] args) throws Exception {
   
   
        //初始化word文档
        Document document = new Document(PageSize.A4)