Package org.springframework.jdbc.support

Class JdbcUtils

java.lang.Object
org.springframework.jdbc.support.JdbcUtils
public abstract class JdbcUtils extends Object
Generic utility methods for working with JDBC. Mainly for internal use within the framework, but also useful for custom JDBC access code.
Author:
Thomas Risberg, Juergen Hoeller

  • Field Details

    • TYPE_UNKNOWN

      public static final int TYPE_UNKNOWN
      Constant that indicates an unknown (or unspecified) SQL type.
      See Also:

  • Constructor Details

    • JdbcUtils

      public JdbcUtils()

  • Method Details

    • closeConnection

      public static void closeConnection(@Nullable Connection con)
      Close the given JDBC Connection and ignore any thrown exception. This is useful for typical finally blocks in manual JDBC code.
      Parameters:
      con - the JDBC Connection to close (may be null)

    • closeStatement

      public static void closeStatement(@Nullable Statement stmt)
      Close the given JDBC Statement and ignore any thrown exception. This is useful for typical finally blocks in manual JDBC code.
      Parameters:
      stmt - the JDBC Statement to close (may be null)

    • closeResultSet

      public static void closeResultSet(@Nullable ResultSet rs)
      Close the given JDBC ResultSet and ignore any thrown exception. This is useful for typical finally blocks in manual JDBC code.
      Parameters:
      rs - the JDBC ResultSet to close (may be null)

    • getResultSetValue

      @Nullable public static Object getResultSetValue(ResultSet rs, int index, @Nullable Class<?> requiredType) throws SQLException
      Retrieve a JDBC column value from a ResultSet, using the specified value type.

      Uses the specifically typed ResultSet accessor methods, falling back to getResultSetValue(java.sql.ResultSet, int) for unknown types.

      Note that the returned value may not be assignable to the specified required type, in case of an unknown type. Calling code needs to deal with this case appropriately, e.g. throwing a corresponding exception.

      Parameters:
      rs - is the ResultSet holding the data
      index - is the column index
      requiredType - the required value type (may be null)
      Returns:
      the value object (possibly not of the specified required type, with further conversion steps necessary)
      Throws:
      SQLException - if thrown by the JDBC API
      See Also:

    • getResultSetValue

      @Nullable public static Object getResultSetValue(ResultSet rs, int index) throws SQLException
      Retrieve a JDBC column value from a ResultSet, using the most appropriate value type. The returned value should be a detached value object, not having any ties to the active ResultSet: in particular, it should not be a Blob or Clob object but rather a byte array or String representation, respectively.

      Uses the getObject(index) method, but includes additional "hacks" to get around Oracle 10g returning a non-standard object for its TIMESTAMP datatype and a java.sql.Date for DATE columns leaving out the time portion: These columns will explicitly be extracted as standard java.sql.Timestamp object.

      Parameters:
      rs - is the ResultSet holding the data
      index - is the column index
      Returns:
      the value object
      Throws:
      SQLException - if thrown by the JDBC API
      See Also:

    • extractDatabaseMetaData

      public static <T> T extractDatabaseMetaData(DataSource dataSource, DatabaseMetaDataCallback<T> action) throws MetaDataAccessException
      Extract database meta-data via the given DatabaseMetaDataCallback.

      This method will open a connection to the database and retrieve its meta-data. Since this method is called before the exception translation feature is configured for a DataSource, this method can not rely on SQLException translation itself.

      Any exceptions will be wrapped in a MetaDataAccessException. This is a checked exception and any calling code should catch and handle this exception. You can just log the error and hope for the best, but there is probably a more serious error that will reappear when you try to access the database again.

      Parameters:
      dataSource - the DataSource to extract meta-data for
      action - callback that will do the actual work
      Returns:
      object containing the extracted information, as returned by the DatabaseMetaDataCallback's processMetaData method
      Throws:
      MetaDataAccessException - if meta-data access failed
      See Also:

    • extractDatabaseMetaData

      @Deprecated public static <T> T extractDatabaseMetaData(DataSource dataSource, String metaDataMethodName) throws MetaDataAccessException
      Deprecated.
      as of 5.2.9, in favor of extractDatabaseMetaData(DataSource, DatabaseMetaDataCallback) with a lambda expression or method reference and a generically typed result
      Call the specified method on DatabaseMetaData for the given DataSource, and extract the invocation result.
      Parameters:
      dataSource - the DataSource to extract meta-data for
      metaDataMethodName - the name of the DatabaseMetaData method to call
      Returns:
      the object returned by the specified DatabaseMetaData method
      Throws:
      MetaDataAccessException - if we couldn't access the DatabaseMetaData or failed to invoke the specified method
      See Also:

    • supportsBatchUpdates

      public static boolean supportsBatchUpdates(Connection con)
      Return whether the given JDBC driver supports JDBC 2.0 batch updates.

      Typically invoked right before execution of a given set of statements: to decide whether the set of SQL statements should be executed through the JDBC 2.0 batch mechanism or simply in a traditional one-by-one fashion.

      Logs a warning if the "supportsBatchUpdates" methods throws an exception and simply returns false in that case.

      Parameters:
      con - the Connection to check
      Returns:
      whether JDBC 2.0 batch updates are supported
      See Also:

    • commonDatabaseName

      @Nullable public static String commonDatabaseName(@Nullable String source)
      Extract a common name for the target database in use even if various drivers/platforms provide varying names at runtime.
      Parameters:
      source - the name as provided in database meta-data
      Returns:
      the common name to be used (e.g. "DB2" or "Sybase")

    • isNumeric

      public static boolean isNumeric(int sqlType)
      Check whether the given SQL type is numeric.
      Parameters:
      sqlType - the SQL type to be checked
      Returns:
      whether the type is numeric

    • resolveTypeName

      @Nullable public static String resolveTypeName(int sqlType)
      Resolve the standard type name for the given SQL type, if possible.
      Parameters:
      sqlType - the SQL type to resolve
      Returns:
      the corresponding constant name in Types (e.g. "VARCHAR"/"NUMERIC"), or null if not resolvable
      Since:
      5.2

    • lookupColumnName

      public static String lookupColumnName(ResultSetMetaData resultSetMetaData, int columnIndex) throws SQLException
      Determine the column name to use. The column name is determined based on a lookup using ResultSetMetaData.

      This method implementation takes into account recent clarifications expressed in the JDBC 4.0 specification:

      columnLabel - the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column.

      Parameters:
      resultSetMetaData - the current meta-data to use
      columnIndex - the index of the column for the look up
      Returns:
      the column name to use
      Throws:
      SQLException - in case of lookup failure

    • convertUnderscoreNameToPropertyName

      public static String convertUnderscoreNameToPropertyName(@Nullable String name)
      Convert a column name with underscores to the corresponding property name using "camel case". A name like "customer_number" would match a "customerNumber" property name.
      Parameters:
      name - the column name to be converted
      Returns:
      the name using "camel case"