Package net.java.ao.db

Class PostgreSQLDatabaseProvider

java.lang.Object
net.java.ao.DatabaseProvider
net.java.ao.db.PostgreSQLDatabaseProvider
All Implemented Interfaces:
Disposable
public class PostgreSQLDatabaseProvider extends DatabaseProvider

  • Constructor Details

  • Method Details

    • parseValue

      public Object parseValue(int type, String value)
      Description copied from class: DatabaseProvider

      Parses the database-agnostic String value relevant to the specified SQL type in int form (as defined by Types and returns the Java value which corresponds. This method is completely database-agnostic, as are all of all of its delegate methods.

      WARNING: This method is being considered for removal to another class (perhaps TypeManager?) as it is not a database-specific function and thus confuses the purpose of this class. Do not rely upon it heavily. (better yet, don't rely on it at all from external code. It's not designed to be part of the public API)

      Overrides:
      parseValue in class DatabaseProvider
      Parameters:
      type - The JDBC integer type of the database field against which to parse the value.
      value - The database-agnostic String value to parse into a proper Java object with respect to the specified SQL type.
      Returns:
      A Java value which corresponds to the specified String.

    • getTables

      public ResultSet getTables(Connection conn) throws SQLException
      Description copied from class: DatabaseProvider

      Returns a result set of all of the tables (and associated meta) in the database. The fields of the result set must correspond with those specified in the DatabaseMetaData#getTables(String, String, String, String[]) method. In fact, the default implementation merely calls this method passing (null, null, "", null). For databases (such as PostgreSQL) where this is unsuitable, different parameters can be specified to the getTables method in the override, or an entirely new implementation written, as long as the result set corresponds in fields to the JDBC spec.

      Overrides:
      getTables in class DatabaseProvider
      Parameters:
      conn - The connection to use in retrieving the database tables.
      Returns:
      A result set of tables (and meta) corresponding in fields to the JDBC specification.
      Throws:
      SQLException
      See Also:

    • renderAutoIncrement

      protected String renderAutoIncrement()
      Description copied from class: DatabaseProvider

      Generates the DDL fragment required to specify an INTEGER field as auto-incremented. For databases which do not support such flags (which is just about every database exception MySQL), "" is an acceptable return value. This method should never return null as it would cause the field rendering method to throw a NullPointerException.

      Overrides:
      renderAutoIncrement in class DatabaseProvider

    • renderFieldType

      protected String renderFieldType(DDLField field)
      Description copied from class: DatabaseProvider
      Renders the database-specific DDL type for the field in question. This method merely delegates to the DatabaseProvider.convertTypeToString(TypeInfo) method, passing the field type. Thus, it is rarely necessary (if ever) to override this method. It may be deprecated in a future release.
      Overrides:
      renderFieldType in class DatabaseProvider
      Parameters:
      field - The field which contains the type to be rendered.
      Returns:
      The database-specific type DDL rendering.

    • renderValue

      protected String renderValue(Object value)
      Description copied from class: DatabaseProvider
      Renders the given Java instance in a database-specific way. This method handles special cases such as Calendar, Boolean (which is always rendered as 0/1), functions, null and numbers. All other values are rendered (by default) as 'value.toString()' (the String value enclosed within single quotes). Implementations are encouraged to override this method as necessary.
      Overrides:
      renderValue in class DatabaseProvider
      Parameters:
      value - The Java instance to be rendered as a database literal.
      Returns:
      The database-specific String rendering of the instance in question.
      See Also:

    • renderUnique

      protected String renderUnique(UniqueNameConverter uniqueNameConverter, DDLTable table, DDLField field)
      Description copied from class: DatabaseProvider
      Renders the UNIQUE constraint as defined by the database-specific DDL syntax. This method is a delegate of other, more complex methods such as DatabaseProvider.renderField(net.java.ao.schema.NameConverters, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField, net.java.ao.DatabaseProvider.RenderFieldOptions). The default implementation just returns UNIQUE. Implementations may override this method to return an empty String if the database in question does not support the constraint.
      Overrides:
      renderUnique in class DatabaseProvider
      Returns:
      The database-specific rendering of UNIQUE.

    • handleBlob

      public Object handleBlob(ResultSet res, Class<?> type, String field) throws SQLException
      Overrides:
      handleBlob in class DatabaseProvider
      Throws:
      SQLException

    • renderAlterTableChangeColumn

      protected Iterable<SQLAction> renderAlterTableChangeColumn(NameConverters nameConverters, DDLTable table, DDLField oldField, DDLField field)
      Description copied from class: DatabaseProvider

      Generates the database-specific DDL statements required to change the given column from its old specification to the given DDL value. This method will also generate the appropriate statements to remove old triggers and functions, as well as add new ones according to the requirements of the new field definition.

      The default implementation of this method functions in the manner specified by the MySQL database. Some databases will have to perform more complicated actions (such as dropping and re-adding the field) in order to satesfy the same use-case. Such databases should print a warning to stderr to ensure that the end-developer is aware of such restrictions.

      Thus, the specification for this method allows for data loss. Nevertheless, if the database supplies a mechanism to accomplish the task without data loss, it should be applied.

      For maximum flexibility, the default implementation of this method only deals with the dropping and addition of functions and triggers. The actual generation of the ALTER TABLE statement is done in the DatabaseProvider.renderAlterTableChangeColumnStatement(net.java.ao.schema.NameConverters, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField, net.java.ao.schema.ddl.DDLField, net.java.ao.DatabaseProvider.RenderFieldOptions) method.

      Overrides:
      renderAlterTableChangeColumn in class DatabaseProvider
      table - The table containing the column to change.
      oldField - The old column definition.
      field - The new column definition (defining the resultant DDL). @return An array of DDL statements to be executed.
      See Also:
      • #getTriggerNameForField(net.java.ao.schema.TriggerNameConverter, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField)
      • #getFunctionNameForField(net.java.ao.schema.TriggerNameConverter, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField)
      • #renderFunctionForField(net.java.ao.schema.TriggerNameConverter, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField)
      • #renderTriggerForField(net.java.ao.schema.TriggerNameConverter, net.java.ao.schema.SequenceNameConverter, net.java.ao.schema.ddl.DDLTable, net.java.ao.schema.ddl.DDLField)

    • renderAlterTableDropKey

      protected SQLAction renderAlterTableDropKey(DDLForeignKey key)
      Description copied from class: DatabaseProvider
      Generates the database-specific DDL statement required to remove a foreign key from a table. For databases which do not support such a statement, a warning should be printed to stderr and a null value returned. This method assumes that the DatabaseProvider.renderForeignKey(DDLForeignKey) method properly names the foreign key according to the DDLForeignKey.getFKName() method.
      Overrides:
      renderAlterTableDropKey in class DatabaseProvider
      Parameters:
      key - The foreign key to be removed. As this instance contains all necessary data (such as domestic table, field, etc), no additional parameters are required.
      Returns:
      A DDL statement to be executed, or null.

    • renderCreateIndex

      protected SQLAction renderCreateIndex(IndexNameConverter indexNameConverter, DDLIndex index)
      Description copied from class: DatabaseProvider
      Generates the database-specific DDL statement required to create a new index. The syntax for this operation is highly standardized and thus it is unlikely this method will be overridden. If the database in question does not support indexes, a warning should be printed to stderr and null returned.
      Overrides:
      renderCreateIndex in class DatabaseProvider
      index - The index to create. This single instance contains all of the data necessary to create the index, thus no separate parameters (such as a DDLTable) are required.
      Returns:
      A DDL statement to be executed.

    • renderDropIndex

      protected SQLAction renderDropIndex(IndexNameConverter indexNameConverter, DDLIndex index)
      Description copied from class: DatabaseProvider
      Generates the database-specific DDL statement required to drop an index. The syntax for this operation is highly standardized and thus it is unlikely this method will be overridden. If the database in question does not support indexes, a warning should be printed to stderr and null returned.
      Overrides:
      renderDropIndex in class DatabaseProvider
      index - The index to drop. This single instance contains all of the data necessary to drop the index, thus no separate parameters (such as a DDLTable) are required.
      Returns:
      A DDL statement to be executed, or null.

    • insertReturningKey

      public <T extends RawEntity<K>, K> K insertReturningKey(EntityManager manager, Connection conn, Class<T> entityType, Class<K> pkType, String pkField, boolean pkIdentity, String table, DBParam... params) throws SQLException
      Description copied from class: DatabaseProvider

      Generates an INSERT statement to be used to create a new row in the database, returning the primary key value. This method also invokes the delegate method, #executeInsertReturningKey(EntityManager, java.sql.Connection, Class, String, String, DBParam...) passing the appropriate parameters and query. This method is required because some databases do not support the JDBC parameter RETURN_GENERATED_KEYS (such as HSQLDB and PostgreSQL). Also, some databases (such as MS SQL Server) require odd tricks to support explicit value passing to auto-generated fields. This method should take care of any extra queries or odd SQL generation required to implement both auto-generated primary key returning, as well as explicit primary key value definition.

      Overriding implementations of this method should be sure to use the Connection instance passed to the method, not a new instance generated using the DatabaseProvider.getConnection() method. This is because this method is in fact a delegate invoked by EntityManager as part of the entity creation process and may be part of a transaction, a bulk creation or some more complicated operation. Both optimization and usage patterns on the API dictate that the specified connection instance be used. Implementations may assume that the given connection instance is never null.

      The default implementation of this method should be sufficient for any fully compliant ANSI SQL database with a properly implemented JDBC driver. Note that this method should not not actually execute the SQL it generates, but pass it on to the #executeInsertReturningKey(EntityManager, java.sql.Connection, Class, String, String, DBParam...) method, allowing for functional delegation and better extensibility. However, this method may execute any additional statements required to prepare for the INSERTion (as in the case of MS SQL Server which requires some config parameters to be set on the database itself prior to INSERT).

      Overrides:
      insertReturningKey in class DatabaseProvider
      Parameters:
      manager - The EntityManager which was used to dispatch the INSERT in question.
      conn - The connection to be used in the eventual execution of the generated SQL statement.
      entityType - The Java class of the entity.
      pkType - The Java type of the primary key value. Can be used to perform a linear search for a specified primary key value in the params list. The return value of the method must be of the same type.
      pkField - The database field which is the primary key for the table in question. Can be used to perform a linear search for a specified primary key value in the params list.
      pkIdentity - Flag indicating whether or not the primary key field is auto-incremented by the database (IDENTITY field).
      table - The name of the table into which the row is to be INSERTed.
      params - A varargs array of parameters to be passed to the INSERT statement. This may include a specified value for the primary key.
      Throws:
      SQLException - If the INSERT fails in the delegate method, or if any additional statements fail with an exception.
      See Also:
      • #executeInsertReturningKey(EntityManager, java.sql.Connection, Class, String, String, DBParam...)

    • executeInsertReturningKey

      protected <T extends RawEntity<K>, K> K executeInsertReturningKey(EntityManager manager, Connection conn, Class<T> entityType, Class<K> pkType, String pkField, String sql, DBParam... params) throws SQLException
      Description copied from class: DatabaseProvider

      Delegate method to execute an INSERT statement returning any auto-generated primary key values. This method is primarily designed to be called as a delegate from the #insertReturningKey(EntityManager, Connection, Class, String, boolean, String, DBParam...) method. The idea behind this method is to allow custom implementations to override this method to potentially execute other statements (such as getting the next value in a sequence) rather than the default implementaiton which uses the JDBC constant, RETURN_GENERATED_KEYS. Any database which has a fully-implemented JDBC driver should have no problems with the default implementation of this method.

      Part of the design behind splitting insertReturningKey and executeInsertReturningKey is so that logic for generating the actual INSERT statement need not be duplicated throughout the code and in custom implementations providing trivial changes to the default algorithm. This method should avoid actually generating SQL if at all possible.

      This method should iterate through the passed DBParam(s) to ensure that no primary key value was explicitly specified. If one was, it should be used in leiu of one which is auto-generated by the database. Also, it is this value which should be returned if specified, rather than the value which would have been generated or null. As such, this method should always return exactly the value of the primary key field in the row which was just inserted, regardless of what that value may be.

      In cases where the database mechanism for getting the next primary key value is not thread safe, this method should be declared synchronized, or some thread synchronization technique employed. Unfortunately, it is not always possible to ensure that no other INSERT could (potentially) "steal" the expected value out from under the algorithm. Such scenarios are to be avoided when possible, but the algorithm need not take extremely escoteric concurrency cases into account. (see the HSQLDB provider for an example of such a less-than-thorough asynchronous algorithm)

      IMPORTANT: The INSERT Statement must use the specified connection, rather than a new one retrieved from DatabaseProvider.getConnection() or equivalent. This is because the INSERT may be part of a bulk insertion, a transaction, or possibly another such operation. It is also important to note that this method should not close the connection. Doing so could cause the entity creation algorithm to fail at a higher level up the stack.

      Overrides:
      executeInsertReturningKey in class DatabaseProvider
      Parameters:
      manager - The EntityManager which was used to dispatch the INSERT in question.
      conn - The database connection to use in executing the INSERT statement.
      entityType - The Java class of the entity.
      pkType - The Java class type of the primary key field (for use both in searching the params as well as performing value conversion of auto-generated DB values into proper Java instances).
      pkField - The database field which is the primary key for the table in question. Can be used to perform a linear search for a specified primary key value in the params list.
      params - A varargs array of parameters to be passed to the INSERT statement. This may include a specified value for the primary key. @throws SQLException If the INSERT fails in the delegate method, or if any additional statements fail with an exception.
      Throws:
      SQLException
      See Also:
      • #insertReturningKey(EntityManager, Connection, Class, String, boolean, String, DBParam...)

    • getReservedWords

      protected Set<String> getReservedWords()
      Description copied from class: DatabaseProvider
      Retrieves the set of all reserved words for the underlying database. The set returns should be speculative, meaning that it should include any possible reserved words, not just those for a particular version. As an implementation guideline, the Set instance returned from this method should guarentee O(1) lookup times, otherwise ORM performance will suffer greatly.
      Specified by:
      getReservedWords in class DatabaseProvider
      Returns:
      A set of upper case reserved words specific to the database.

    • shouldQuoteID

      protected boolean shouldQuoteID(String id)
      Description copied from class: DatabaseProvider
      Determines whether or not the specified identifier should be quoted before transmission to the underlying database. The default implementation transforms the identifier into all-upper-case and checks the result against DatabaseProvider.getReservedWords(). Databases with more complicated rules regarding quoting should provide a custom implementation of this method.
      Overrides:
      shouldQuoteID in class DatabaseProvider
      Parameters:
      id - The identifier to check against the quoting rules.
      Returns:
      true if the specified identifier is invalid under the relevant quoting rules, otherwise false.

    • shouldQuoteTableName

      protected boolean shouldQuoteTableName(String tableName)
      Description copied from class: DatabaseProvider
      Determines whether or not the table name should be quoted before transmission to the underlying database. The default implementation does the same as DatabaseProvider.shouldQuoteID(String) but can be overridden by subclasses.
      Overrides:
      shouldQuoteTableName in class DatabaseProvider
      Parameters:
      tableName - The table name to check against the quoting rules.
      Returns:
      true if the table name is invalid under the relevant quoting rules, otherwise false.

    • handleUpdateError

      public void handleUpdateError(String sql, SQLException e) throws SQLException
      Description copied from class: DatabaseProvider
      Tells whether this exception should be ignored when running an updated statement. Typically, errors on dropping non-existing objects should be ignored.
      Overrides:
      handleUpdateError in class DatabaseProvider
      e - the SQLException that occured.
      Throws:
      SQLException - throws the SQLException if it should not be ignored.