org.apache.cayenne.ejbql.parser.EJBQLFromItem Maven / Gradle / Ivy
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package org.apache.cayenne.ejbql.parser;
import org.apache.cayenne.ejbql.EJBQLBaseVisitor;
import org.apache.cayenne.ejbql.EJBQLExpression;
import org.apache.cayenne.ejbql.EJBQLExpressionVisitor;
/**
* @since 3.0
*/
public class EJBQLFromItem extends SimpleNode {
public EJBQLFromItem(int id) {
super(id);
}
/**
* Returns an id generated from the entity name. It is used when no user-specified id
* exists.
*/
public String getSyntheticId() {
int len = getChildrenCount();
if (len < 1) {
return null;
}
final String[] entityNames = new String[1];
getChild(0).visit(new EJBQLBaseVisitor() {
@Override
public boolean visitIdentificationVariable(EJBQLExpression expression) {
entityNames[0] = expression.getText();
return false;
}
});
if (entityNames[0] == null) {
return null;
}
// id's are case insensitive, while entity names are. Using simple encoding to
// transform the entity name in such way that two entities that differ only in
// capitalization would produce different lowercase ids
StringBuilder id = new StringBuilder(entityNames[0].length() + 2);
for (int i = 0; i < entityNames[0].length(); i++) {
char c = entityNames[0].charAt(i);
if (Character.isUpperCase(c)) {
id.append('%').append(Character.toLowerCase(c));
}
else {
id.append(c);
}
}
return id.toString();
}
public String getId() {
int len = getChildrenCount();
if (len < 2) {
return getSyntheticId();
}
return jjtGetChild(len - 1).getText();
}
@Override
protected boolean visitNode(EJBQLExpressionVisitor visitor) {
return visitor.visitFromItem(this, -1);
}
@Override
protected boolean visitChild(EJBQLExpressionVisitor visitor, int childIndex) {
return super.visitChild(visitor, childIndex)
&& visitor.visitFromItem(this, childIndex);
}
}