//$Id: OracleJoinFragment.java 15511 2008-11-05 01:46:59Z gbadner $
package org.hibernate.sql;
import java.util.HashSet;
import java.util.Set;
/**
* An Oracle-style (theta) join
*
* @author Jon Lipsky, Gavin King
*/
public class OracleJoinFragment extends JoinFragment {
private StringBuffer afterFrom = new StringBuffer();
private StringBuffer afterWhere = new StringBuffer();
public void addJoin(String tableName, String alias, String[] fkColumns, String[] pkColumns, int joinType) {
addCrossJoin( tableName, alias );
for ( int j = 0; j < fkColumns.length; j++ ) {
setHasThetaJoins( true );
afterWhere.append( " and " )
.append( fkColumns[j] );
if ( joinType == RIGHT_OUTER_JOIN || joinType == FULL_JOIN ) afterWhere.append( "(+)" );
afterWhere.append( '=' )
.append( alias )
.append( '.' )
.append( pkColumns[j] );
if ( joinType == LEFT_OUTER_JOIN || joinType == FULL_JOIN ) afterWhere.append( "(+)" );
}
}
public String toFromFragmentString() {
return afterFrom.toString();
}
public String toWhereFragmentString() {
return afterWhere.toString();
}
public void addJoins(String fromFragment, String whereFragment) {
afterFrom.append( fromFragment );
afterWhere.append( whereFragment );
}
public JoinFragment copy() {
OracleJoinFragment copy = new OracleJoinFragment();
copy.afterFrom = new StringBuffer( afterFrom.toString() );
copy.afterWhere = new StringBuffer( afterWhere.toString() );
return copy;
}
public void addCondition(String alias, String[] columns, String condition) {
for ( int i = 0; i < columns.length; i++ ) {
afterWhere.append( " and " )
.append( alias )
.append( '.' )
.append( columns[i] )
.append( condition );
}
}
public void addCrossJoin(String tableName, String alias) {
afterFrom.append( ", " )
.append( tableName )
.append( ' ' )
.append( alias );
}
public void addCondition(String alias, String[] fkColumns, String[] pkColumns) {
throw new UnsupportedOperationException();
}
public boolean addCondition(String condition) {
return addCondition( afterWhere, condition );
}
public void addFromFragmentString(String fromFragmentString) {
afterFrom.append( fromFragmentString );
}
public void addJoin(String tableName, String alias, String[] fkColumns, String[] pkColumns, int joinType, String on) {
//arbitrary on clause ignored!!
addJoin( tableName, alias, fkColumns, pkColumns, joinType );
if ( joinType == JoinFragment.INNER_JOIN ) {
addCondition( on );
}
else if ( joinType == JoinFragment.LEFT_OUTER_JOIN ) {
addLeftOuterJoinCondition( on );
}
else {
throw new UnsupportedOperationException( "join type not supported by OracleJoinFragment (use Oracle9iDialect)" );
}
}
/**
* This method is a bit of a hack, and assumes
* that the column on the "right" side of the
* join appears on the "left" side of the
* operator, which is extremely wierd if this
* was a normal join condition, but is natural
* for a filter.
*/
private void addLeftOuterJoinCondition(String on) {
StringBuffer buf = new StringBuffer( on );
for ( int i = 0; i < buf.length(); i++ ) {
char character = buf.charAt( i );
boolean isInsertPoint = OPERATORS.contains( new Character( character ) ) ||
( character == ' ' && buf.length() > i + 3 && "is ".equals( buf.substring( i + 1, i + 4 ) ) );
if ( isInsertPoint ) {
buf.insert( i, "(+)" );
i += 3;
}
}
addCondition( buf.toString() );
}
private static final Set OPERATORS = new HashSet();
static {
OPERATORS.add( new Character( '=' ) );
OPERATORS.add( new Character( '<' ) );
OPERATORS.add( new Character( '>' ) );
}
}
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