// $Id: LiteralProcessor.java 11258 2007-03-07 22:41:22Z [email protected] $
package org.hibernate.hql.ast.util;
import org.hibernate.MappingException;
import org.hibernate.QueryException;
import org.hibernate.HibernateException;
import org.hibernate.dialect.Dialect;
import org.hibernate.hql.QueryTranslator;
import org.hibernate.hql.antlr.HqlSqlTokenTypes;
import org.hibernate.hql.antlr.SqlTokenTypes;
import org.hibernate.hql.ast.HqlSqlWalker;
import org.hibernate.hql.ast.InvalidPathException;
import org.hibernate.hql.ast.tree.DotNode;
import org.hibernate.hql.ast.tree.FromClause;
import org.hibernate.hql.ast.tree.IdentNode;
import org.hibernate.persister.entity.Queryable;
import org.hibernate.sql.InFragment;
import org.hibernate.type.LiteralType;
import org.hibernate.type.Type;
import org.hibernate.type.TypeFactory;
import org.hibernate.util.ReflectHelper;
import antlr.SemanticException;
import antlr.collections.AST;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import java.math.BigDecimal;
import java.text.DecimalFormat;
/**
* A delegate that handles literals and constants for HqlSqlWalker, performing the token replacement functions and
* classifying literals.
*
* @author josh Sep 2, 2004 7:15:30 AM
*/
public class LiteralProcessor implements HqlSqlTokenTypes {
/**
* Indicates that Float and Double literal values should
* be treated using the SQL "exact" format (i.e., '.001')
*/
public static final int EXACT = 0;
/**
* Indicates that Float and Double literal values should
* be treated using the SQL "approximate" format (i.e., '1E-3')
*/
public static final int APPROXIMATE = 1;
/**
* In what format should Float and Double literal values be sent
* to the database?
* @see #EXACT, #APPROXIMATE
*/
public static int DECIMAL_LITERAL_FORMAT = EXACT;
private static final Log log = LogFactory.getLog( LiteralProcessor.class );
private HqlSqlWalker walker;
public LiteralProcessor(HqlSqlWalker hqlSqlWalker) {
this.walker = hqlSqlWalker;
}
public boolean isAlias(String alias) {
FromClause from = walker.getCurrentFromClause();
while ( from.isSubQuery() ) {
if ( from.containsClassAlias(alias) ) {
return true;
}
from = from.getParentFromClause();
}
return from.containsClassAlias(alias);
}
public void processConstant(AST constant, boolean resolveIdent) throws SemanticException {
// If the constant is an IDENT, figure out what it means...
boolean isIdent = ( constant.getType() == IDENT || constant.getType() == WEIRD_IDENT );
if ( resolveIdent && isIdent && isAlias( constant.getText() ) ) { // IDENT is a class alias in the FROM.
IdentNode ident = ( IdentNode ) constant;
// Resolve to an identity column.
ident.resolve(false, true);
}
else { // IDENT might be the name of a class.
Queryable queryable = walker.getSessionFactoryHelper().findQueryableUsingImports( constant.getText() );
if ( isIdent && queryable != null ) {
constant.setText( queryable.getDiscriminatorSQLValue() );
}
// Otherwise, it's a literal.
else {
processLiteral( constant );
}
}
}
public void lookupConstant(DotNode node) throws SemanticException {
String text = ASTUtil.getPathText( node );
Queryable persister = walker.getSessionFactoryHelper().findQueryableUsingImports( text );
if ( persister != null ) {
// the name of an entity class
final String discrim = persister.getDiscriminatorSQLValue();
node.setDataType( persister.getDiscriminatorType() );
if ( InFragment.NULL.equals(discrim) || InFragment.NOT_NULL.equals(discrim) ) {
throw new InvalidPathException( "subclass test not allowed for null or not null discriminator: '" + text + "'" );
}
else {
setSQLValue( node, text, discrim ); //the class discriminator value
}
}
else {
Object value = ReflectHelper.getConstantValue( text );
if ( value == null ) {
throw new InvalidPathException( "Invalid path: '" + text + "'" );
}
else {
setConstantValue( node, text, value );
}
}
}
private void setSQLValue(DotNode node, String text, String value) {
if ( log.isDebugEnabled() ) {
log.debug( "setSQLValue() " + text + " -> " + value );
}
node.setFirstChild( null ); // Chop off the rest of the tree.
node.setType( SqlTokenTypes.SQL_TOKEN );
node.setText(value);
node.setResolvedConstant( text );
}
private void setConstantValue(DotNode node, String text, Object value) {
if ( log.isDebugEnabled() ) {
log.debug( "setConstantValue() " + text + " -> " + value + " " + value.getClass().getName() );
}
node.setFirstChild( null ); // Chop off the rest of the tree.
if ( value instanceof String ) {
node.setType( SqlTokenTypes.QUOTED_STRING );
}
else if ( value instanceof Character ) {
node.setType( SqlTokenTypes.QUOTED_STRING );
}
else if ( value instanceof Byte ) {
node.setType( SqlTokenTypes.NUM_INT );
}
else if ( value instanceof Short ) {
node.setType( SqlTokenTypes.NUM_INT );
}
else if ( value instanceof Integer ) {
node.setType( SqlTokenTypes.NUM_INT );
}
else if ( value instanceof Long ) {
node.setType( SqlTokenTypes.NUM_LONG );
}
else if ( value instanceof Double ) {
node.setType( SqlTokenTypes.NUM_DOUBLE );
}
else if ( value instanceof Float ) {
node.setType( SqlTokenTypes.NUM_FLOAT );
}
else {
node.setType( SqlTokenTypes.CONSTANT );
}
Type type;
try {
type = TypeFactory.heuristicType( value.getClass().getName() );
}
catch ( MappingException me ) {
throw new QueryException( me );
}
if ( type == null ) {
throw new QueryException( QueryTranslator.ERROR_CANNOT_DETERMINE_TYPE + node.getText() );
}
try {
LiteralType literalType = ( LiteralType ) type;
Dialect dialect = walker.getSessionFactoryHelper().getFactory().getDialect();
node.setText( literalType.objectToSQLString( value, dialect ) );
}
catch ( Exception e ) {
throw new QueryException( QueryTranslator.ERROR_CANNOT_FORMAT_LITERAL + node.getText(), e );
}
node.setDataType( type );
node.setResolvedConstant( text );
}
public void processBoolean(AST constant) {
// TODO: something much better - look at the type of the other expression!
// TODO: Have comparisonExpression and/or arithmeticExpression rules complete the resolution of boolean nodes.
String replacement = ( String ) walker.getTokenReplacements().get( constant.getText() );
if ( replacement != null ) {
constant.setText( replacement );
}
else {
boolean bool = "true".equals( constant.getText().toLowerCase() );
Dialect dialect = walker.getSessionFactoryHelper().getFactory().getDialect();
constant.setText( dialect.toBooleanValueString(bool) );
}
}
private void processLiteral(AST constant) {
String replacement = ( String ) walker.getTokenReplacements().get( constant.getText() );
if ( replacement != null ) {
if ( log.isDebugEnabled() ) {
log.debug( "processConstant() : Replacing '" + constant.getText() + "' with '" + replacement + "'" );
}
constant.setText( replacement );
}
}
public void processNumeric(AST literal) {
if ( literal.getType() == NUM_INT || literal.getType() == NUM_LONG ) {
literal.setText( determineIntegerRepresentation( literal.getText(), literal.getType() ) );
}
else if ( literal.getType() == NUM_FLOAT || literal.getType() == NUM_DOUBLE ) {
literal.setText( determineDecimalRepresentation( literal.getText(), literal.getType() ) );
}
else {
log.warn( "Unexpected literal token type [" + literal.getType() + "] passed for numeric processing" );
}
}
private String determineIntegerRepresentation(String text, int type) {
try {
if ( type == NUM_INT ) {
try {
return Integer.valueOf( text ).toString();
}
catch( NumberFormatException e ) {
log.trace( "could not format incoming text [" + text + "] as a NUM_INT; assuming numeric overflow and attempting as NUM_LONG" );
}
}
String literalValue = text;
if ( literalValue.endsWith( "l" ) || literalValue.endsWith( "L" ) ) {
literalValue = literalValue.substring( 0, literalValue.length() - 1 );
}
return Long.valueOf( literalValue ).toString();
}
catch( Throwable t ) {
throw new HibernateException( "Could not parse literal [" + text + "] as integer", t );
}
}
public String determineDecimalRepresentation(String text, int type) {
String literalValue = text;
if ( type == NUM_FLOAT ) {
if ( literalValue.endsWith( "f" ) || literalValue.endsWith( "F" ) ) {
literalValue = literalValue.substring( 0, literalValue.length() - 1 );
}
}
else if ( type == NUM_DOUBLE ) {
if ( literalValue.endsWith( "d" ) || literalValue.endsWith( "D" ) ) {
literalValue = literalValue.substring( 0, literalValue.length() - 1 );
}
}
BigDecimal number = null;
try {
number = new BigDecimal( literalValue );
}
catch( Throwable t ) {
throw new HibernateException( "Could not parse literal [" + text + "] as big-decimal", t );
}
return formatters[ DECIMAL_LITERAL_FORMAT ].format( number );
}
private static interface DecimalFormatter {
String format(BigDecimal number);
}
private static class ExactDecimalFormatter implements DecimalFormatter {
public String format(BigDecimal number) {
return number.toString();
}
}
private static class ApproximateDecimalFormatter implements DecimalFormatter {
private static final String FORMAT_STRING = "#0.0E0";
public String format(BigDecimal number) {
try {
// TODO : what amount of significant digits need to be supported here?
// - from the DecimalFormat docs:
// [significant digits] = [minimum integer digits] + [maximum fraction digits]
DecimalFormat jdkFormatter = new DecimalFormat( FORMAT_STRING );
jdkFormatter.setMinimumIntegerDigits( 1 );
jdkFormatter.setMaximumFractionDigits( Integer.MAX_VALUE );
return jdkFormatter.format( number );
}
catch( Throwable t ) {
throw new HibernateException( "Unable to format decimal literal in approximate format [" + number.toString() + "]", t );
}
}
}
private static final DecimalFormatter[] formatters = new DecimalFormatter[] {
new ExactDecimalFormatter(),
new ApproximateDecimalFormatter()
};
}
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