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JavaXT
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Connection ClassUsed to open and close a connection to a database and execute queries.
Constructors Connection( )
Public MethodsgetConnectionSpeed( ) returns long Used to retrieve the time it took to open the database connection (in milliseconds) getConnection( ) returns java.sql.Connection Used to retrieve the java.sql.Connection for this Connection open( String ConnectionString ) returns boolean Used to open a connection to the database using a JDBC connection string. Returns true if the connection was opened successfully.
open( Database database ) returns boolean Used to open a connection to the database using a javaxt.sql.Database. Returns true if the connection was opened successfully. open( java.sql.Connection conn, Database database ) returns boolean Used establish a connection to the database using a previously opened java.sql.Connection. Returns true if the connection is open.
open( java.sql.Connection conn ) returns boolean Used establish a connection to the database using a previously opened java.sql.Connection. Returns true if the connection is open. close( ) returns void Used to close a connection to the database, freeing up server resources. It is imperative that the database connection is closed after it is no longer needed, especially if the connection came from a ConnectionPool. That said, this class implements the AutoCloseable interface so you do not have to call this method if the connection was opened as part of a "try" statement. Example:
try (javaxt.sql.Connection conn = database.getConnection()){
}
catch(Exception e){
e.printStackTrace();
} getRecords( String sql ) returns Iterable<javaxt.sql.Record> Used to execute a SQL statement and returns Records as an iterator. Example:
for (javaxt.sql.Record record : conn.getRecords("select id from contacts")){
System.out.println(record.get(0));
} Note that records returned by this method are read-only.getRecords( String sql, Map<String, Object> props ) returns Iterable<javaxt.sql.Record> Used to execute a SQL statement and returns a Records as an iterator. Example:
for (javaxt.sql.Record record : conn.getRecords(
"select first_name, last_name from contacts",
new HashMap<String, Object>() {{
put("readOnly", true);
put("fetchSize", 1000);
}}
))
{
System.out.println(record.get("first_name") + " " + record.get("last_name"));
}
getRecord( String sql ) returns javaxt.sql.Record Returns a single record from the database. Example:
javaxt.sql.Record record = conn.getRecord("select count(*) from contacts");
if (record!=null) System.out.println(record.get(0)); Note that records returned by this method are read-only.getRecordset( String sql, Map<String, Object> props ) returns Recordset Used to execute a SQL statement and return an open Recordset. The caller must explicitly close the Recordset when finished or invoke the getRecordset() method it in a try/catch statement.
getRecordset( String sql, boolean readOnly ) returns Recordset Used to execute a SQL statement and return an open Recordset. The caller must explicitly close the Recordset when finished or invoke the getRecordset() method it in a try/catch statement. Example usage:
try (javaxt.sql.Connection conn = db.getConnection()){
//Open recordset
try (javaxt.sql.Recordset rs = conn.getRecordset("select * from contacts")){
//Iterate through the records
while (rs.next()){
//Do something with the record. Example:
System.out.println(rs.getValue(0));
}
}
}
catch(Exception e){
e.printStackTrace();
}
getRecordset( String sql ) returns Recordset Used to execute a SQL statement and return an open Recordset. The caller must explicitly close the Recordset when finished or invoke the getRecordset() method it in a try/catch statement. See the other getRecordset() for an example. Note that records returned by this method are read-only. execute( String sql ) returns void Used to execute a prepared sql statement (e.g. "delete from my_table"). getDatabase( ) returns Database Used to return database information associated with this connection. |
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