This is the central class in the JDBC core package.
It simplifies the use of JDBC and helps to avoid common errors.
It executes core JDBC workflow, leaving application code to provide SQL
and extract results. This class executes SQL queries or updates, initiating
iteration over ResultSets and catching JDBC exceptions and translating
them to the generic, more informative exception hierarchy defined in the
org.springframework.dao package.
Code using this class need only implement callback interfaces, giving
them a clearly defined contract. The PreparedStatementCreator callback
interface creates a prepared statement given a Connection provided by this
class, providing SQL and any necessary parameters. The RowCallbackHandler
interface extracts values from each row of a ResultSet.
Can be used within a service implementation via direct instantiation
with a DataSource reference, or get prepared in an application context
and given to services as bean reference. Note: The DataSource should
always be configured as a bean in the application context, in the first case
given to the service directly, in the second case to the prepared template.
The motivation and design of this class is discussed
in detail in
Expert One-On-One J2EE Design and Development
by Rod Johnson (Wrox, 2002).
Because this class is parameterizable by the callback interfaces and
the SQLExceptionTranslator interface, it isn't necessary to subclass it.
All operations performed by this class are logged at debug level.
applyStatementSettings
protected void applyStatementSettings(Statement stmt)
throws SQLException Prepare the given JDBC Statement (or PreparedStatement or CallableStatement),
applying statement settings such as fetch size, max rows, and query timeout.
stmt - the JDBC Statement to prepare
createConnectionProxy
protected Connection createConnectionProxy(Connection con)
Create a close-suppressing proxy for the given JDBC Connection.
Called by the
execute method.
The proxy also prepares returned JDBC Statements, applying
statement settings such as fetch size, max rows, and query timeout.
con - the JDBC Connection to create a proxy for
getFetchSize
public int getFetchSize()
Return the fetch size specified for this JdbcTemplate.
getMaxRows
public int getMaxRows()
Return the maximum number of rows specified for this JdbcTemplate.
getSingleColumnRowMapper
protected RowMapper getSingleColumnRowMapper(Class<T> requiredType)
Create a new RowMapper for reading result objects from a single column.
requiredType - the type that each result object is expected to match
isIgnoreWarnings
public boolean isIgnoreWarnings()
Return whether or not we ignore SQLWarnings. Default is "true".
query
protected Object query(PreparedStatementCreator psc,
PreparedStatementSetter pss,
ResultSetExtractor rse)
throws DataAccessException Query using a prepared statement, allowing for a PreparedStatementCreator
and a PreparedStatementSetter. Most other query methods use this method,
but application code will always work with either a creator or a setter.
psc - Callback handler that can create a PreparedStatement given a
Connectionpss - object that knows how to set values on the prepared statement.
If this is null, the SQL will be assumed to contain no bind parameters.rse - object that will extract results.
- an arbitrary result object, as returned by the ResultSetExtractor
View More Examples of queryForInt(String sql,Object[] args)
1:
2: private JdbcTemplate jdbcTemplate;
3:
4: ...
5: public BoxOfficeDBHelper(JdbcTemplate jdbcTemplate) {
6: this.jdbcTemplate = jdbcTemplate;
7: ...
8: Object[] args = new Object[] { new Long(seatId), new Long(bookingId) };
9: return jdbcTemplate.queryForInt(sql, args) > 0;
10: }
11: ...
12: Object[] args = new Object[] { new Long(bookingId) };
13: int count = jdbcTemplate.queryForInt(sql, args);
View Full Code Here
View More Examples of queryForLong(String sql,Object[] args)
1:
2: private JdbcTemplate jdbcTemplate;
3:
4: ...
5: public BoxOfficeDBHelper(JdbcTemplate jdbcTemplate) {
6: this.jdbcTemplate = jdbcTemplate;
7: ...
8: };
9: return jdbcTemplate.queryForLong(sql, args);
10: }
11: ...
12:
13: return jdbcTemplate.queryForLong(sql, args);
View Full Code Here
View More Examples of queryForRowSet(String sql)
1: import ;
2: import ;
3: import ;
4: ...
5: List runSql(String sql){
6: JdbcTemplate jt = new JdbcTemplate(ds);
7: ...
8: SqlRowSet rows = jt.queryForRowSet(sql);
9: List result = new ArrayList();
View Full Code Here
setFetchSize
public void setFetchSize(int fetchSize)
Set the fetch size for this JdbcTemplate. This is important for processing
large result sets: Setting this higher than the default value will increase
processing speed at the cost of memory consumption; setting this lower can
avoid transferring row data that will never be read by the application.
Default is 0, indicating to use the JDBC driver's default.
setIgnoreWarnings
public void setIgnoreWarnings(boolean ignoreWarnings)
Set whether or not we want to ignore SQLWarnings.
Default is "true".
setMaxRows
public void setMaxRows(int maxRows)
Set the maximum number of rows for this JdbcTemplate. This is important
for processing subsets of large result sets, avoiding to read and hold
the entire result set in the database or in the JDBC driver if we're
never interested in the entire result in the first place (for example,
when performing searches that might return a large number of matches).
Default is 0, indicating to use the JDBC driver's default.
setNativeJdbcExtractor
public void setNativeJdbcExtractor(NativeJdbcExtractor extractor)
Set a NativeJdbcExtractor to extract native JDBC objects from wrapped handles.
Useful if native Statement and/or ResultSet handles are expected for casting
to database-specific implementation classes, but a connection pool that wraps
JDBC objects is used (note: any pool will return wrapped Connections).
View More Examples of update(String sql)
1: import ;
2: import ;
3: import ;
4: ...
5: public void initBase() {
6: JdbcTemplate tpl = new JdbcTemplate();
7: tpl.setDataSource(this.getDataSource());
8: ...
9: try {
10: tpl.update(dropSql);
11: logger.info("'countries' table deleted");
12: ...
13:
14: tpl.update(createSql);
View Full Code Here
View More Examples of update(String sql,Object[] args)
1:
2: private JdbcTemplate jdbcTemplate;
3:
4: ...
5: public BoxOfficeDBHelper(JdbcTemplate jdbcTemplate) {
6: this.jdbcTemplate = jdbcTemplate;
7: ...
8: Object[] args = new Object[] { new Long(id), name };
9: jdbcTemplate.update(sql, args);
10: }
11: ...
12: };
13: jdbcTemplate.update(sql, args);
View Full Code Here
View More Examples of update(String sql,PreparedStatementSetter pss)
1:
2: private JdbcTemplate jdbcTemplate;
3:
4: ...
5: public BoxOfficeDBHelper(JdbcTemplate jdbcTemplate) {
6: this.jdbcTemplate = jdbcTemplate;
7: ...
8: Object[] args = new Object[] { new Long(id), name };
9: jdbcTemplate.update(sql, args);
10: }
11: ...
12: };
13: jdbcTemplate.update(sql, args);
View Full Code Here
View More Examples of update(PreparedStatementCreator psc)
1: import ;
2: import ;
3: import ;
4: ...
5: public void initBase() {
6: JdbcTemplate tpl = new JdbcTemplate();
7: tpl.setDataSource(this.getDataSource());
8: ...
9: try {
10: tpl.update(dropSql);
11: logger.info("'countries' table deleted");
12: ...
13:
14: tpl.update(createSql);
View Full Code Here
View More Examples of update(PreparedStatementCreator psc,KeyHolder generatedKeyHolder)
1:
2: private JdbcTemplate jdbcTemplate;
3:
4: ...
5: public BoxOfficeDBHelper(JdbcTemplate jdbcTemplate) {
6: this.jdbcTemplate = jdbcTemplate;
7: ...
8: Object[] args = new Object[] { new Long(id), name };
9: jdbcTemplate.update(sql, args);
10: }
11: ...
12: };
13: jdbcTemplate.update(sql, args);
View Full Code Here