用途：用于获取指定数据库中表以及栏目的各项信息（包括字段名、注释、类型、是否为空等）
该类用于存储数据库信息（用户名、密码等）
该类用于存储栏目的各项信息，按需拓展。
- 获取数据库连接
public static Connection getConnection(CfsDatabase cfsDatabase) {
Connection conn = null;
try {
conn = DriverManager.getConnection(cfsDatabase.getUrl(), cfsDatabase.getUserName(), cfsDatabase.getPassword());
} catch (SQLException e) {
LOGGER.error("获取数据库连接失败", e);
}
return conn;
}
-
获取数据库下所有表名
public static List<String> getTableNames(CfsDatabase cfsDatabase) {
List<String> tableNames = new ArrayList<>();
Connection conn = getConnection(cfsDatabase);
ResultSet rs = null;
try {
//获取数据库的元数据
DatabaseMetaData db = conn.getMetaData();
//从元数据中获取到所有的表名
rs = db.getTables("lwj_odin_v2", null, null, new String[]{"TABLE"});
while (rs.next()) {
tableNames.add(rs.getString(3));
}
} catch (SQLException e) {
LOGGER.error("获取数据库表信息失败", e);
} finally {
try {
rs.close();
closeConnection(conn);
} catch (SQLException e) {
LOGGER.error("关闭数据库连接失败", e);
}
}
return tableNames;
}
-
获取表中字段和注释的关系并存入map对象
public static Map<String,String> getColumnComments(String tableName, CfsDatabase cfsDatabase) {
//用于存储字段与注释
Map<String,String>columnMap=new HashMap<>();
//与数据库的连接
Connection conn = getConnection(cfsDatabase);
PreparedStatement pStemt = null;
String tableSql = SQL + tableName;
ResultSet rs = null;
try {
ps = conn.prepareStatement(tableSql);
rs = ps.executeQuery("show full columns from " + tableName);
while (rs.next()) {
columnMap.put(rs.getString("Field"),rs.getString("Comment"));
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (rs != null) {
try {
rs.close();
closeConnection(conn);
} catch (SQLException e) {
LOGGER.error("数据库操作失败", e);
}
}
}
return columnMap;
}
-
获取表中所有字段信息
public static List<DatabaseInfo> getColumnNames(String tableName,CfsDatabase cfsDatabase) {
//获取字段和注释的关联关系
Map<String,String> columnMap=DatabaseUtil.getColumnComments(tableName,cfsDatabase);
List<DatabaseInfo> databaseInfos = new ArrayList<>();
//与数据库的连接
Connection conn = getConnection(cfsDatabase);
PreparedStatement pStemt = null;
String tableSql = SQL + tableName;
try {
ps= conn.prepareStatement(tableSql);
//结果集元数据
ResultSetMetaData rsmd = ps.getMetaData();
//表列数
int size = rsmd.getColumnCount();
for (int i = 1; i <= size; i++) {
DatabaseInfo databaseInfo=new DatabaseInfo();
//获取字段名称
databaseInfo.setFieldName(rsmd.getColumnName(i));
//获取字段类型
databaseInfo.setType(rsmd.getColumnTypeName(i));
//字段是否为空
databaseInfo.setEmptyStatus(String.valueOf(rsmd.isNullable(i)));
//字段注释
databaseInfo.setAnnotation(columnMap.get(rsmd.getColumnName(i)));
databaseInfos.add(databaseInfo);
}
} catch (SQLException e) {
LOGGER.error("获取数据库表的列信息失败", e);
} finally {
if (pStemt != null) {
try {
pStemt.close();
closeConnection(conn);
} catch (SQLException e) {
LOGGER.error("关闭数据库连接失败", e);
}
}
}
return databaseInfos;
}