使用JDBC获取各数据库的Meta信息——表以及对应的列
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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;
}
}
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 = "以上是关于使用JDBC获取各数据库的Meta信息——表以及对应的列的主要内容，如果未能解决你的问题，请参考以下文章