package com.cn.common.utils;import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Properties;
import oracle.jdbc.OracleConnection;/*** 这个类主要用于手动的辅助写与数据库交互的XML文件，打印一些固定格式的信息，用于写增删改查的数据库SQL语句* @author Administrator**/
public class MetaDataTest {/*** 主方法，获得表的结构信息* @param args*/public static void main(String[] args){try {Class.forName("oracle.jdbc.driver.OracleDriver");String url = "THE URL";String username="THE USERNAME";String password="THE PASSWORD";try {Properties props =new Properties();props.put("remarksReporting","true");/** 获得数据库连接，通过URL/USERNAME/PASSWORD，注意，要确定数据的服务是开启的*/Connection conn = DriverManager.getConnection(url,username,password);/** 设置连接属性,使得可获取到列的REMARK(备注)*/((OracleConnection)conn).setRemarksReporting(true); DatabaseMetaData dmd = conn.getMetaData();System.out.println("=============================================The database infor======================================================");                // 数据库名:System.out.println("数据库名称:" + dmd.getDatabaseProductName());// 数据库版本号:System.out.println("数据库版本号  :"+ dmd.getDatabaseProductVersion());// 驱动程序System.out.println("数据库驱动程序 :" + dmd.getDriverName());// 驱动版本System.out.println("数据库驱动版本:" + dmd.getDriverVersion());
System.out.println("=============================================The users infor=========================================================");                //打印当前数据库的所有用户名称
                getAllSchemas(dmd);
System.out.println("=============================================The tables infor========================================================");                                //打印当前数据库用户下的所有表信息getAllTableList(dmd,"THE SCHEMA");
System.out.println("=============================================The table infor=========================================================");                                //打印当前用户当前表结构信息getTableColumns(dmd,"THE SCHEMA","THE TABLE");} catch (SQLException e) {e.printStackTrace();}} catch (ClassNotFoundException e) {e.printStackTrace();}}/** * 获得表或视图中的列信息*/  public static void getTableColumns(DatabaseMetaData dbMetaData,String schemaName, String tableName){  try{        ResultSet rs = dbMetaData.getColumns(null, schemaName, tableName, "%");              while (rs.next()){  String tableCat = rs.getString("TABLE_CAT");//表目录（可能为空）              String tableSchemaName = rs.getString("TABLE_SCHEM");//表的架构（可能为空）     String tableName_ = rs.getString("TABLE_NAME");//表名  String columnName = rs.getString("COLUMN_NAME");//列名  int dataType = rs.getInt("DATA_TYPE"); //对应的java.sql.Types类型     String dataTypeName = rs.getString("TYPE_NAME");//java.sql.Types类型名称  int columnSize = rs.getInt("COLUMN_SIZE");//列大小int decimalDigits = rs.getInt("DECIMAL_DIGITS");//小数位数  int numPrecRadix = rs.getInt("NUM_PREC_RADIX");//基数（通常是10进制的） int nullAble = rs.getInt("NULLABLE");//是否允许为null  String remarks = rs.getString("REMARKS");//列描述String columnDef = rs.getString("COLUMN_DEF");//默认int sqlDataType = rs.getInt("SQL_DATA_TYPE");//sql数据类型  int sqlDatetimeSub = rs.getInt("SQL_DATETIME_SUB");   //SQL日期时间 int charOctetLength = rs.getInt("CHAR_OCTET_LENGTH");   //char类型的列中的字节长度int ordinalPosition = rs.getInt("ORDINAL_POSITION");  //表中列的索引（从1开始）String propName = colNameToPropName(columnName);
System.out.println("=============================================The bean property infor=================================================");                                                    System.out.println("private String " + propName+";");
System.out.println("=============================================The column map infor====================================================");                    System.out.println("<result column=\""+columnName+"\" property=\""+propName+"\" jdbcType=\"NVARCHAR\" />");
System.out.println("=============================================The input property infor==================================================");System.out.println("#"+propName+"#,");
System.out.println("=============================================The map property  infor===============================================");System.out.println(columnName+"=#"+propName+"#,");
System.out.println("=============================================The bean property remarks infor=========================================");System.out.println("<tbl:th width=\"80\" delim=\"true\" field=\""+propName+"\">"+remarks+"</tbl:th>");
System.out.println("=============================================The property map infor==================================================");System.out.println("<tbl:td delim=\"true\">${element."+propName+"}</tbl:td>");/** * ISO规则用来确定某一列的为空性 * YES--如果该参数可以包括空值* NO--如果参数不能包含空值* 空字符串---如果参数为空性是未知的*/  String isNullAble = rs.getString("IS_NULLABLE");  /** * 指示此列是否是自动增长的* 1--如果该列是自动的* 2--如果不是自动递增的* 空字符串--如果不能确定它是否是自动增长的* 列是自动递增的参数是未知的*/
//                    String isAutoincrement = rs.getString("IS_AUTOINCREMENT");
System.out.println("=============================================The column map infor=====================================================");                      System.out.println(tableCat + "-" + tableSchemaName + "-" + tableName_ + "-" + columnName + "-"    + dataType + "-" + dataTypeName + "-" + columnSize + "-" + decimalDigits + "-" + numPrecRadix     + "-" + nullAble + "-" + remarks + "-" + columnDef + "-" + sqlDataType + "-" + sqlDatetimeSub     + charOctetLength + "-" + ordinalPosition + "-" + isNullAble + "-" +"");     }     } catch (SQLException e){  e.printStackTrace();     }  }  /**   * 获得数据库中所有用户名称   * @param dbMetaData */    public static void getAllSchemas(DatabaseMetaData dbMetaData){  try{  ResultSet rs = dbMetaData.getSchemas();   while (rs.next()){     String tableSchem = rs.getString("TABLE_SCHEM");     System.out.println(tableSchem);     }     } catch (SQLException e){  e.printStackTrace();     }     }     /** * 获得指定用户下面的表信息数据*/  public static void getAllTableList(DatabaseMetaData dbMetaData,String schemaName) {  try {  /** table type. Typical types are "TABLE", "VIEW", "SYSTEM TABLE", "GLOBAL TEMPORARY", "LOCAL TEMPORARY", "ALIAS", "SYNONYM".  */String[] types = { "TABLE" };  ResultSet rs = dbMetaData.getTables(null, schemaName, "%", types);  while (rs.next()) {  String tableName = rs.getString("TABLE_NAME");  //表名称 String tableType = rs.getString("TABLE_TYPE");  //表类型String remarks = rs.getString("REMARKS");       //表备注System.out.println(tableName + "-" + tableType + "-" + remarks);  }  } catch (SQLException e) {  e.printStackTrace();  }  }/*** 将数据库表中的列名转换成JavaBean的属性名称，转换规则是采用驼峰式的命名规则* @param columnName* @return*/private static String colNameToPropName(String columnName){String result="";String name = columnName.toLowerCase();String[] data = name.split("_");for(int i=0;i<data.length;i++){if(i==0){result  = data[i];}else{result  += data[i].replaceFirst(data[i].substring(0, 1), data[i].substring(0, 1).toUpperCase());}}return result;}
}