使用JDBC获取各数据库的Meta信息——表以及对应的列


先贴代码,作为草稿:

第一个是工具类, MapUtil.java

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * map转换工具
 */
public class MapUtil {
	
	/**
	 * 将List中的Key转换为小写
	 * @param list 返回新对象
	 * @return
	 */
	public static List<Map<String, Object>> convertKeyList2LowerCase(List<Map<String, Object>> list){
		if(null==list) {
			return null;
		}
		List<Map<String, Object>> resultList = new ArrayList<Map<String,Object>>();
		//
		Iterator<Map<String, Object>> iteratorL = list.iterator();
		while (iteratorL.hasNext()) {
			Map<String, Object> map = (Map<String, Object>) iteratorL.next();
			//
			Map<String, Object> result = convertKey2LowerCase(map);
			if(null != result){
				resultList.add(result);
			}
		}
		//
		return resultList;
	}
	/**
	 * 转换单个map,将key转换为小写. 
	 * @param map 返回新对象
	 * @return
	 */
	public static Map<String, Object> convertKey2LowerCase(Map<String, Object> map){
		if(null==map) {
			return null;
		}
		Map<String, Object> result = new HashMap<String, Object>();
		//
		Set<String> keys  = map.keySet();
		//
		Iterator<String> iteratorK = keys.iterator();
		while (iteratorK.hasNext()) {
			String key = (String) iteratorK.next();
			Object value = map.get(key);
			if(null == key){
				continue;
			}
			//
			String keyL = key.toLowerCase();
			result.put(keyL, value);
		}
		return result;
	}
	/**
	 * 将List中Map的Key转换为小写.
	 * @param list
	 * @return
	 */
	public static List<Map<String, Object>> trimListKeyValue(List<Map<String, Object>> list){
		if(null==list) {
			return null;
		}
		List<Map<String, Object>> resultList = new ArrayList<Map<String,Object>>();
		//
		Iterator<Map<String, Object>> iteratorL = list.iterator();
		while (iteratorL.hasNext()) {
			Map<String, Object> map = (Map<String, Object>) iteratorL.next();
			//
			Map<String, Object> result = trimKeyValue(map);
			if(null != result){
				resultList.add(result);
			}
		}
		//
		return resultList;
	}
	/**
	 * 转换单个map,将key转换为小写. 
	 * @param map 返回新对象
	 * @return
	 */
	public static Map<String, Object> trimKeyValue(Map<String, Object> map){
		if(null==map) {
			return null;
		}
		Map<String, Object> result = new HashMap<String, Object>();
		//
		Set<String> keys  = map.keySet();
		//
		Iterator<String> iteratorK = keys.iterator();
		while (iteratorK.hasNext()) {
			String key = (String) iteratorK.next();
			Object value = map.get(key);
			if(null == key){
				continue;
			}
			//
			String keyT = key.trim();
			if(value instanceof String){
				String valueT = String.valueOf(value).trim();
				result.put(keyT, valueT);
			} else {
				result.put(keyT, value);
			}
		}
		return result;
	}
}


然后是具体的实现工具类,使用了阿里巴巴的 fastjson 工具包;里面的测试类可以忽略

import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Properties;

import com.alibaba.fastjson.JSONArray;

/**
 * 需要注意,想要有表字段描述信息,获取连接时需要指定某些特殊属性<br/> 
 * 数据交换-工具类
 */
public class DBMSMetaUtil {


	/**
	 * 数据库类型,枚举
	 * 
	 */
	public static enum DATABASETYPE {
		ORACLE, MYSQL, SQLSERVER, SQLSERVER2005, DB2, INFORMIX, SYBASE, OTHER, EMPTY
	}

	/**
	 * 根据字符串,判断数据库类型
	 * 
	 * @param databasetype
	 * @return
	 */
	public static DATABASETYPE parseDATABASETYPE(String databasetype) {
		// 空类型
		if (null == databasetype || databasetype.trim().length() < 1) {
			return DATABASETYPE.EMPTY;
		}
		// 截断首尾空格,转换为大写
		databasetype = databasetype.trim().toUpperCase();
		// Oracle数据库
		if (databasetype.contains("ORACLE")) {
			//
			return DATABASETYPE.ORACLE;
		}
		// MYSQL 数据库
		if (databasetype.contains("MYSQL")) {
			//
			return DATABASETYPE.MYSQL;
		}
		// SQL SERVER 数据库
		if (databasetype.contains("SQL") && databasetype.contains("SERVER")) {
			//
			if (databasetype.contains("2005") || databasetype.contains("2008") || databasetype.contains("2012")) {

        		try {
					Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
				} catch (ClassNotFoundException e) {
					e.printStackTrace();
				}
				
				return DATABASETYPE.SQLSERVER2005;
			} else {
				try {
					// 注册 JTDS
					Class.forName("net.sourceforge.jtds.jdbc.Driver");
				} catch (ClassNotFoundException e) {
					e.printStackTrace();
				}
				return DATABASETYPE.SQLSERVER;
			}
		}
		// 下面的这几个没有经过实践测试, 判断可能不准确
		// DB2 数据库
		if (databasetype.contains("DB2")) {
			//
			return DATABASETYPE.DB2;
		}
		// INFORMIX 数据库
		if (databasetype.contains("INFORMIX")) {
			//
			return DATABASETYPE.INFORMIX;
		}
		// SYBASE 数据库
		if (databasetype.contains("SYBASE")) {
			//
			return DATABASETYPE.SYBASE;
		}

		// 默认,返回其他
		return DATABASETYPE.OTHER;
	}

	/**
	 * 列出数据库的所有表
	 */
	// 可以参考: http://www.cnblogs.com/chinafine/articles/1847205.html
	public static List<Map<String, Object>> listTables(String databasetype, String ip, String port, String dbname,
			String username, String password) {
		// 去除首尾空格
		databasetype = trim(databasetype);
		ip = trim(ip);
		port = trim(port);
		dbname = trim(dbname);
		username = trim(username);
		password = trim(password);
		//
		DATABASETYPE dbtype = parseDATABASETYPE(databasetype);
		//
		List<Map<String, Object>> result = null;
		String url = concatDBURL(dbtype, ip, port, dbname);
		Connection conn = getConnection(url, username, password);
		// Statement stmt = null;
		ResultSet rs = null;
		//
		try {
			// 这句话我也不懂是什么意思... 好像没什么用
			conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
			// 获取Meta信息对象
			DatabaseMetaData meta = conn.getMetaData();
			// 数据库
			String catalog = null;
			// 数据库的用户
			String schemaPattern = null;// meta.getUserName();
			// 表名
			String tableNamePattern = null;//
			// types指的是table、view
			String[] types = { "TABLE" };
			// Oracle
			if (DATABASETYPE.ORACLE.equals(dbtype)) {
				schemaPattern = username;
				if (null != schemaPattern) {
					schemaPattern = schemaPattern.toUpperCase();
				}
				// 查询
				rs = meta.getTables(catalog, schemaPattern, tableNamePattern, types);
			} else if (DATABASETYPE.MYSQL.equals(dbtype)) {
				// Mysql查询
				// MySQL 的 table 这一级别查询不到备注信息
				schemaPattern = dbname;
				rs = meta.getTables(catalog, schemaPattern, tableNamePattern, types);
			}  else if (DATABASETYPE.SQLSERVER.equals(dbtype) || DATABASETYPE.SQLSERVER2005.equals(dbtype)) {
				// SqlServer
				tableNamePattern = "%";
				rs = meta.getTables(catalog, schemaPattern, tableNamePattern, types);
			}  else if (DATABASETYPE.DB2.equals(dbtype)) {
				// DB2查询
				schemaPattern = "jence_user";
				tableNamePattern = "%";
				rs = meta.getTables(catalog, schemaPattern, tableNamePattern, types);
			} else if (DATABASETYPE.INFORMIX.equals(dbtype)) {
				// SqlServer
				tableNamePattern = "%";
				rs = meta.getTables(catalog, schemaPattern, tableNamePattern, types);
			} else if (DATABASETYPE.SYBASE.equals(dbtype)) {
				// SqlServer
				tableNamePattern = "%";
				rs = meta.getTables(catalog, schemaPattern, tableNamePattern, types);
			}  else {
				throw new RuntimeException("不认识的数据库类型!");
			}
			//
			result = parseResultSetToMapList(rs);

		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			close(rs);
			close(conn);
		}
		//
		return result;
	}

	/**
	 * 列出表的所有字段
	 */
	public static List<Map<String, Object>> listColumns(String databasetype, String ip, String port, String dbname,
			String username, String password, String tableName) {
		// 去除首尾空格
		databasetype = trim(databasetype);
		ip = trim(ip);
		port = trim(port);
		dbname = trim(dbname);
		username = trim(username);
		password = trim(password);
		tableName = trim(tableName);
		//
		DATABASETYPE dbtype = parseDATABASETYPE(databasetype);
		//
		List<Map<String, Object>> result = null;
		String url = concatDBURL(dbtype, ip, port, dbname);
		Connection conn = getConnection(url, username, password);
		// Statement stmt = null;
		ResultSet rs = null;
		//
		try {
			// 获取Meta信息对象
			DatabaseMetaData meta = conn.getMetaData();
			// 数据库
			String catalog = null;
			// 数据库的用户
			String schemaPattern = null;// meta.getUserName();
			// 表名
			String tableNamePattern = tableName;//
			// 转换为大写
			if (null != tableNamePattern) {
				tableNamePattern = tableNamePattern.toUpperCase();
			}
			// 
			String columnNamePattern = null;
			// Oracle
			if (DATABASETYPE.ORACLE.equals(dbtype)) {
				// 查询
				schemaPattern = username;
				if (null != schemaPattern) {
					schemaPattern = schemaPattern.toUpperCase();
				}
			} else {
				//
			}

			rs = meta.getColumns(catalog, schemaPattern, tableNamePattern, columnNamePattern);
			// TODO 获取主键列,但还没使用
			meta.getPrimaryKeys(catalog, schemaPattern, tableNamePattern);
			//
			result = parseResultSetToMapList(rs);
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			// 关闭资源
			close(rs);
			close(conn);
		}
		//
		return result;
	}

	/**
	 * 根据IP,端口,以及数据库名字,拼接Oracle连接字符串
	 * 
	 * @param ip
	 * @param port
	 * @param dbname
	 * @return
	 */
	public static String concatDBURL(DATABASETYPE dbtype, String ip, String port, String dbname) {
		//
		String url = "";
		// Oracle数据库
		if (DATABASETYPE.ORACLE.equals(dbtype)) {
			//
			url += "jdbc:oracle:thin:@";
			url += ip.trim();
			url += ":" + port.trim();
			url += ":" + dbname;
			
			// 如果需要采用 hotbackup
			String url2 = "";
			url2 = url2+"jdbc:oracle:thin:@(DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = "
					+ ip.trim() +")(PORT ="+ port.trim() +")))(CONNECT_DATA = (SERVICE_NAME ="+dbname+
					")(FAILOVER_MODE = (TYPE = SELECT)(METHOD = BASIC)(RETRIES = 180)(DELAY = 5))))";
			//
			// url = url2;
		} else if (DATABASETYPE.MYSQL.equals(dbtype)) {
			//
			url += "jdbc:mysql://";
			url += ip.trim();
			url += ":" + port.trim();
			url += "/" + dbname;
		} else if (DATABASETYPE.SQLSERVER.equals(dbtype)) {
			//
			url += "jdbc:jtds:sqlserver://";
			url += ip.trim();
			url += ":" + port.trim();
			url += "/" + dbname;
			url += ";tds=8.0;lastupdatecount=true";
		} else if (DATABASETYPE.SQLSERVER2005.equals(dbtype)) {
			//
			url += "jdbc:sqlserver://";
			url += ip.trim();
			url += ":" + port.trim();
			url += "; DatabaseName=" + dbname;
		} else if (DATABASETYPE.DB2.equals(dbtype)) {
			url += "jdbc:db2://";
			url += ip.trim();
			url += ":" + port.trim();
			url += "/" + dbname;
		} else if (DATABASETYPE.INFORMIX.equals(dbtype)) {
			// Infox mix 可能有BUG
			url += "jdbc:informix-sqli://";
			url += ip.trim();
			url += ":" + port.trim();
			url += "/" + dbname;
			// +":INFORMIXSERVER=myserver;user="+bean.getDatabaseuser()+";password="+bean.getDatabasepassword()
		} else if (DATABASETYPE.SYBASE.equals(dbtype)) {
			url += "jdbc:sybase:Tds:";
			url += ip.trim();
			url += ":" + port.trim();
			url += "/" + dbname;
		} else {
			throw new RuntimeException("不认识的数据库类型!");
		}
		//
		return url;
	}

	/**
	 * 获取JDBC连接
	 * 
	 * @param url
	 * @param username
	 * @param password
	 * @return
	 */
	public static Connection getConnection(String url, String username, String password) {
		Connection conn = null;
		try {
			// 不需要加载Driver. Servlet 2.4规范开始容器会自动载入
			// conn = DriverManager.getConnection(url, username, password);
			//
			Properties info =new Properties();
			//
			info.put("user", username);
			info.put("password", password);
			// !!! Oracle 如果想要获取元数据 REMARKS 信息,需要加此参数
			info.put("remarksReporting","true");
			// !!! MySQL 标志位, 获取TABLE元数据 REMARKS 信息
			info.put("useInformationSchema","true");
			// 不知道SQLServer需不需要设置...
			//
			conn = DriverManager.getConnection(url, info);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return conn;
	}

	/**
	 * 将一个未处理的ResultSet解析为Map列表.
	 * 
	 * @param rs
	 * @return
	 */
	public static List<Map<String, Object>> parseResultSetToMapList(ResultSet rs) {
		//
		List<Map<String, Object>> result = new ArrayList<Map<String, Object>>();
		//
		if (null == rs) {
			return null;
		}
		//
		try {
			while (rs.next()) {
				// 
				Map<String, Object> map = parseResultSetToMap(rs);
				//
				if (null != map) {
					result.add(map);
				}
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
		//
		return result;
	}

	/**
	 * 解析ResultSet的单条记录,不进行 ResultSet 的next移动处理
	 * 
	 * @param rs
	 * @return
	 */
	private static Map<String, Object> parseResultSetToMap(ResultSet rs) {
		//
		if (null == rs) {
			return null;
		}
		//
		Map<String, Object> map = new HashMap<String, Object>();
		//
		try {
			ResultSetMetaData meta = rs.getMetaData();
			//
			int colNum = meta.getColumnCount();
			//
			for (int i = 1; i <= colNum; i++) {
				// 列名
				String name = meta.getColumnLabel(i); // i+1
				Object value = rs.getObject(i);
				// 加入属性
				map.put(name, value);
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
		//
		return map;
	}
	
	//
	public static boolean TryLink(String databasetype, String ip, String port, String dbname, String username, String password) {
		//
		DATABASETYPE dbtype = parseDATABASETYPE(databasetype);
		String url = concatDBURL(dbtype, ip, port, dbname);
		Connection conn = null;
		//
		try {
			conn = getConnection(url, username, password);
			if(null == conn){
				return false;
			}
			DatabaseMetaData meta =  conn.getMetaData();
			//
			if(null == meta){
				return false;
			} else {
				// 只有这里返回true
				return true;
			}
		} catch (Exception e) {
			e.printStackTrace();
		} finally{
			close(conn);
		}
		//
		return false;
	}
	//
	public static void close(Connection conn) {
		if(conn!=null) {
			try {
				conn.close();
				conn = null;
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
	}
	//
	public static void close(Statement stmt) {
		if(stmt!=null) {
			try {
				stmt.close();
				stmt = null;
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
	}
	//
	public static void close(ResultSet rs) {
		if(rs!=null) {
			try {
				rs.close();
				rs = null;
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
	}
	//
	public static String trim(String str){
		if(null != str){
			str = str.trim();
		}
		return str;
	}

	public static void main(String[] args) {
		//testLinkOracle();
		//testLinkSQLServer();
		testOracle();
		//testMySQL();
	}

	//
	public static void testLinkOracle() {
		//
		String ip= "192.168.0.100";
		String port= "1521"; 
		String dbname= "orcl"; 
		String username= "username"; 
		String password= "*****pwd";
		String databasetype= "oracle";
		//
		String url = concatDBURL(parseDATABASETYPE(databasetype), ip, port, dbname);
		System.out.println("url="+url);
		//
		boolean result = TryLink(databasetype, ip, port, dbname, username, password);
		//
		System.out.println("result="+result);
	}

	//
	public static void testLinkSQLServer() {
		//
		String ip= "192.168.0.100";
		String port= "1433"; 
		String dbname= "sqlserverdb1"; 
		String username= "sa"; 
		String password= "186957";
		String databasetype= "SQL Server";
		//
		String url = concatDBURL(parseDATABASETYPE(databasetype), ip, port, dbname);
		System.out.println("url="+url);
		//
		boolean result = TryLink(databasetype, ip, port, dbname, username, password);
		//
		System.out.println("result="+result);
	}
	
	
	
	public static void testOracle() {
		//
		String ip = "192.168.0.100";
		String port = "1521";
		String dbname = "orcl";
		String username = "unixsys";
		String password = "orpass";
		//
		String databasetype = "Oracle";
		// DATABASETYPE dbtype = parseDATABASETYPE(databasetype);
		// System.out.println(DATABASETYPE.ORACLE.equals(dbtype));
		//
		String tableName = "DBMS_CODE_CHEME_NEW";

		List<Map<String, Object>> tables = listTables(databasetype, ip, port, dbname, username, password);
		List<Map<String, Object>> columns = listColumns(databasetype, ip, port, dbname, username, password, tableName);
		//
		tables = MapUtil.convertKeyList2LowerCase(tables);
		columns = MapUtil.convertKeyList2LowerCase(columns);
		//
		String jsonT = JSONArray.toJSONString(tables, true);
		System.out.println(jsonT);
		System.out.println("tables.size()=" + tables.size());
		//
		System.out.println("-----------------------------------------" + "-----------------------------------------");
		System.out.println("-----------------------------------------" + "-----------------------------------------");
		//
		String jsonC = JSONArray.toJSONString(columns, true);
		System.out.println(jsonC);
		System.out.println("columns.size()=" + columns.size());
	}
	

	public static void testMySQL() {
		//
		String ip = "127.0.0.1";
		String port = "4050";
		String 
			dbname = "cncounter";
			dbname = "eReqDlG";
		String 
			username = "root";
			username = "6EhSiGpsmSMRr";
		String 
			password = "eoNRNBgRk397mVy";
		//
		String databasetype = "mysql";
		// DATABASETYPE dbtype = parseDATABASETYPE(databasetype);
		// System.out.println(DATABASETYPE.ORACLE.equals(dbtype));
		//
		String tableName = "vote";

		List<Map<String, Object>> tables = listTables(databasetype, ip, port, dbname, username, password);
		List<Map<String, Object>> columns = listColumns(databasetype, ip, port, dbname, username, password, tableName);
		//
		tables = MapUtil.convertKeyList2LowerCase(tables);
		columns = MapUtil.convertKeyList2LowerCase(columns);
		//
		String jsonT = JSONArray.toJSONString(tables, true);
		System.out.println(jsonT);
		System.out.println("tables.size()=" + tables.size());
		//
		System.out.println("-----------------------------------------" + "-----------------------------------------");
		System.out.println("-----------------------------------------" + "-----------------------------------------");
		//
		String jsonC = JSONArray.toJSONString(columns, true);
		System.out.println(jsonC);
		System.out.println("columns.size()=" + columns.size());
	}
	// 演示 DatabaseMetaData
	public static void demoDatabaseMetaData() {
		try {
			Class.forName("com.mysql.jdbc.Driver");
			Connection con = DriverManager.getConnection("jdbc:mysql://localhost/dbtest", "root", "root");
			//
			DatabaseMetaData dmd = con.getMetaData();
			System.out.println("当前数据库是:" + dmd.getDatabaseProductName());
			System.out.println("当前数据库版本:" + dmd.getDatabaseProductVersion());
			System.out.println("当前数据库驱动:" + dmd.getDriverVersion());
			System.out.println("当前数据库URL:" + dmd.getURL());
			System.out.println("当前数据库是否是只读模式?:" + dmd.isReadOnly());
			System.out.println("当前数据库是否支持批量更新?:" + dmd.supportsBatchUpdates());
			System.out.println("当前数据库是否支持结果集的双向移动(数据库数据变动不在ResultSet体现)?:"
					+ dmd.supportsResultSetType(ResultSet.TYPE_SCROLL_INSENSITIVE));
			System.out.println("当前数据库是否支持结果集的双向移动(数据库数据变动会影响到ResultSet的内容)?:"
					+ dmd.supportsResultSetType(ResultSet.TYPE_SCROLL_SENSITIVE));
			System.out.println("========================================");

			ResultSet rs = dmd.getTables(null, null, "%", null);
			System.out.println("表名" + "," + "表类型");
			while (rs.next()) {
				System.out.println(rs.getString("TABLE_NAME") + "," + rs.getString("TABLE_TYPE"));
			}
			System.out.println("========================================");

			rs = dmd.getPrimaryKeys(null, null, "t_student");
			while (rs.next()) {
				System.out.println(rs.getString(3) + "表的主键是:" + rs.getString(4));
			}
			System.out.println("========================================");

			rs = dmd.getColumns(null, null, "t_student", "%");
			System.out.println("t_student表包含的字段:");
			while (rs.next()) {
				System.out.println(rs.getString(4) + " " + rs.getString(6) + "(" + rs.getString(7) + ");");
			}
			System.out.println("========================================");

		} catch (Exception e) {
			System.out.println("数据库操作出现异常");
		}
	}

	// ResultSetMetaData 使用示例
	// 此方法参考 http://blog.csdn.net/yirentianran/article/details/2950321
	public static void demoResultSetMetaData(ResultSetMetaData data) throws SQLException {
		for (int i = 1; i <= data.getColumnCount(); i++) {
			// 获得所有列的数目及实际列数
			int columnCount = data.getColumnCount();
			// 获得指定列的列名
			String columnName = data.getColumnName(i);
			// 获得指定列的列值
			// String columnValue = rs.getString(i);
			// 获得指定列的数据类型
			int columnType = data.getColumnType(i);
			// 获得指定列的数据类型名
			String columnTypeName = data.getColumnTypeName(i);
			// 所在的Catalog名字
			String catalogName = data.getCatalogName(i);
			// 对应数据类型的类
			String columnClassName = data.getColumnClassName(i);
			// 在数据库中类型的最大字符个数
			int columnDisplaySize = data.getColumnDisplaySize(i);
			// 默认的列的标题
			String columnLabel = data.getColumnLabel(i);
			// 获得列的模式
			String schemaName = data.getSchemaName(i);
			// 某列类型的精确度(类型的长度)
			int precision = data.getPrecision(i);
			// 小数点后的位数
			int scale = data.getScale(i);
			// 获取某列对应的表名
			String tableName = data.getTableName(i);
			// 是否自动递增
			boolean isAutoInctement = data.isAutoIncrement(i);
			// 在数据库中是否为货币型
			boolean isCurrency = data.isCurrency(i);
			// 是否为空
			int isNullable = data.isNullable(i);
			// 是否为只读
			boolean isReadOnly = data.isReadOnly(i);
			// 能否出现在where中
			boolean isSearchable = data.isSearchable(i);
			System.out.println(columnCount);
			System.out.println("获得列" + i + "的字段名称:" + columnName);
			// System.out.println("获得列" + i + "的字段值:" + columnValue);
			System.out.println("获得列" + i + "的类型,返回SqlType中的编号:" + columnType);
			System.out.println("获得列" + i + "的数据类型名:" + columnTypeName);
			System.out.println("获得列" + i + "所在的Catalog名字:" + catalogName);
			System.out.println("获得列" + i + "对应数据类型的类:" + columnClassName);
			System.out.println("获得列" + i + "在数据库中类型的最大字符个数:" + columnDisplaySize);
			System.out.println("获得列" + i + "的默认的列的标题:" + columnLabel);
			System.out.println("获得列" + i + "的模式:" + schemaName);
			System.out.println("获得列" + i + "类型的精确度(类型的长度):" + precision);
			System.out.println("获得列" + i + "小数点后的位数:" + scale);
			System.out.println("获得列" + i + "对应的表名:" + tableName);
			System.out.println("获得列" + i + "是否自动递增:" + isAutoInctement);
			System.out.println("获得列" + i + "在数据库中是否为货币型:" + isCurrency);
			System.out.println("获得列" + i + "是否为空:" + isNullable);
			System.out.println("获得列" + i + "是否为只读:" + isReadOnly);
			System.out.println("获得列" + i + "能否出现在where中:" + isSearchable);
		}
	}

}


需要整理后才能发布.


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