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[Hibernate-commits] Hibernate Code SVN: r10221 - in trunk/Hibernate3/src/org/hibernate/dialect: . function
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From: <hib...@li...> - 2006-08-04 18:38:37
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Author: ste...@jb...
Date: 2006-08-04 14:37:47 -0400 (Fri, 04 Aug 2006)
New Revision: 10221
Added:
trunk/Hibernate3/src/org/hibernate/dialect/ResultColumnReferenceStrategy.java
Removed:
trunk/Hibernate3/src/org/hibernate/dialect/function/AnsiTrimEmulationFunction.java
Modified:
trunk/Hibernate3/src/org/hibernate/dialect/DerbyDialect.java
trunk/Hibernate3/src/org/hibernate/dialect/Dialect.java
Log:
added ResultColumnReferenceStrategy (not yet being utilized);
Derby trim() function (w/o capability to specify replacement character)
Modified: trunk/Hibernate3/src/org/hibernate/dialect/DerbyDialect.java
===================================================================
--- trunk/Hibernate3/src/org/hibernate/dialect/DerbyDialect.java 2006-08-04 18:25:19 UTC (rev 10220)
+++ trunk/Hibernate3/src/org/hibernate/dialect/DerbyDialect.java 2006-08-04 18:37:47 UTC (rev 10221)
@@ -2,12 +2,22 @@
package org.hibernate.dialect;
import org.hibernate.Hibernate;
+import org.hibernate.QueryException;
+import org.hibernate.HibernateException;
+import org.hibernate.engine.Mapping;
+import org.hibernate.engine.SessionFactoryImplementor;
+import org.hibernate.type.Type;
import org.hibernate.dialect.function.VarArgsSQLFunction;
import org.hibernate.dialect.function.AnsiTrimEmulationFunction;
+import org.hibernate.dialect.function.SQLFunction;
+import org.hibernate.dialect.function.SQLFunctionTemplate;
import org.hibernate.id.TableHiLoGenerator;
import org.hibernate.sql.CaseFragment;
import org.hibernate.sql.DerbyCaseFragment;
+import java.util.List;
+import java.util.ArrayList;
+
/**
* @author Simon Johnston
*
@@ -21,7 +31,7 @@
public DerbyDialect() {
super();
registerFunction( "concat", new VarArgsSQLFunction( Hibernate.STRING, "(","||",")" ) );
- registerFunction( "trim", new AnsiTrimEmulationFunction() );
+ registerFunction( "trim", new DerbyTrimFunctionEmulation() );
}
/**
@@ -38,18 +48,18 @@
return new DerbyCaseFragment();
}
- public boolean dropConstraints() {
- return true;
+ public boolean dropConstraints() {
+ return true;
}
-
+
public Class getNativeIdentifierGeneratorClass() {
return TableHiLoGenerator.class;
}
-
+
public boolean supportsSequences() {
return false;
}
-
+
public boolean supportsLimit() {
return false;
}
@@ -60,5 +70,124 @@
public String getQuerySequencesString() {
return null ;
- }
+ }
+
+ /**
+ * A specialized function template to emulate the ANSI trim function on Derby DB
+ * since it does not support the full trim specification. However, we cannot even
+ * fully emulate it because there is not standard 'replace' function either. :(
+ */
+ public static class DerbyTrimFunctionEmulation implements SQLFunction {
+ private static final SQLFunction LEADING_SPACE_TRIM = new SQLFunctionTemplate( Hibernate.STRING, "ltrim( ?1 )");
+ private static final SQLFunction TRAILING_SPACE_TRIM = new SQLFunctionTemplate( Hibernate.STRING, "rtrim( ?1 )");
+ private static final SQLFunction BOTH_SPACE_TRIM = new SQLFunctionTemplate( Hibernate.STRING, "ltrim( rtrim( ?1 ) )");
+ private static final SQLFunction BOTH_SPACE_TRIM_FROM = new SQLFunctionTemplate( Hibernate.STRING, "ltrim( rtrim( ?2 ) )");
+
+ public Type getReturnType(Type columnType, Mapping mapping) throws QueryException {
+ return Hibernate.STRING;
+ }
+
+ public boolean hasArguments() {
+ return true;
+ }
+
+ public boolean hasParenthesesIfNoArguments() {
+ return false;
+ }
+
+ public String render(List args, SessionFactoryImplementor factory) throws QueryException {
+ // according to both the ANSI-SQL and EJB3 specs, trim can either take
+ // exactly one parameter or a variable number of parameters between 1 and 4.
+ // from the SQL spec:
+ //
+ // <trim function> ::=
+ // TRIM <left paren> <trim operands> <right paren>
+ //
+ // <trim operands> ::=
+ // [ [ <trim specification> ] [ <trim character> ] FROM ] <trim source>
+ //
+ // <trim specification> ::=
+ // LEADING
+ // | TRAILING
+ // | BOTH
+ //
+ // If only <trim specification> is omitted, BOTH is assumed;
+ // if <trim character> is omitted, space is assumed
+ if ( args.size() == 1 ) {
+ // we have the form: trim(trimSource)
+ // so we trim leading and trailing spaces
+ return BOTH_SPACE_TRIM.render( args, factory );
+ }
+ else if ( "from".equalsIgnoreCase( ( String ) args.get( 0 ) ) ) {
+ // we have the form: trim(from trimSource).
+ // This is functionally equivalent to trim(trimSource)
+ return BOTH_SPACE_TRIM_FROM.render( args, factory );
+ }
+ else {
+ // otherwise, a trim-specification and/or a trim-character
+ // have been specified; we need to decide which options
+ // are present and "do the right thing"
+ boolean leading = true; // should leading trim-characters be trimmed?
+ boolean trailing = true; // should trailing trim-characters be trimmed?
+ String trimCharacter = null; // the trim-character
+ String trimSource = null; // the trim-source
+
+ // potentialTrimCharacterArgIndex = 1 assumes that a
+ // trim-specification has been specified. we handle the
+ // exception to that explicitly
+ int potentialTrimCharacterArgIndex = 1;
+ String firstArg = ( String ) args.get( 0 );
+ if ( "leading".equalsIgnoreCase( firstArg ) ) {
+ trailing = false;
+ }
+ else if ( "trailing".equalsIgnoreCase( firstArg ) ) {
+ leading = false;
+ }
+ else if ( "both".equalsIgnoreCase( firstArg ) ) {
+ }
+ else {
+ potentialTrimCharacterArgIndex = 0;
+ }
+
+ String potentialTrimCharacter = ( String ) args.get( potentialTrimCharacterArgIndex );
+ if ( "from".equalsIgnoreCase( potentialTrimCharacter ) ) {
+ trimCharacter = "' '";
+ trimSource = ( String ) args.get( potentialTrimCharacterArgIndex + 1 );
+ }
+ else if ( potentialTrimCharacterArgIndex + 1 >= args.size() ) {
+ trimCharacter = "' '";
+ trimSource = potentialTrimCharacter;
+ }
+ else {
+ trimCharacter = potentialTrimCharacter;
+ if ( "from".equalsIgnoreCase( ( String ) args.get( potentialTrimCharacterArgIndex + 1 ) ) ) {
+ trimSource = ( String ) args.get( potentialTrimCharacterArgIndex + 2 );
+ }
+ else {
+ trimSource = ( String ) args.get( potentialTrimCharacterArgIndex + 1 );
+ }
+ }
+
+ List argsToUse = null;
+ argsToUse = new ArrayList();
+ argsToUse.add( trimSource );
+ argsToUse.add( trimCharacter );
+
+ if ( trimCharacter.equals( "' '" ) ) {
+ if ( leading && trailing ) {
+ return BOTH_SPACE_TRIM.render( argsToUse, factory );
+ }
+ else if ( leading ) {
+ return LEADING_SPACE_TRIM.render( argsToUse, factory );
+ }
+ else {
+ return TRAILING_SPACE_TRIM.render( argsToUse, factory );
+ }
+ }
+ else {
+ throw new HibernateException( "cannot specify trim character when using Derby as Derby does not support the ANSI trim function, not does it support a replace function to properly emmulate it" );
+ }
+ }
+ }
+ }
}
Modified: trunk/Hibernate3/src/org/hibernate/dialect/Dialect.java
===================================================================
--- trunk/Hibernate3/src/org/hibernate/dialect/Dialect.java 2006-08-04 18:25:19 UTC (rev 10220)
+++ trunk/Hibernate3/src/org/hibernate/dialect/Dialect.java 2006-08-04 18:37:47 UTC (rev 10221)
@@ -1079,4 +1079,49 @@
// return false here, as most databases do not properly support this construct...
return false;
}
+
+ /**
+ * Which strategy should be used to reference columns in the "result" when
+ * performing sorting (i.e. when processing an order by). This is
+ * defined by ANSI SQL as the manner in which columns can be referred to in the
+ * group-by, having, and order-by clauses.
+ * <p/>
+ * The default is to use {@link ResultColumnReferenceStrategy#SOURCE} since that
+ * is the most performant.
+ *
+ * @return The strategy to use.
+ */
+ public ResultColumnReferenceStrategy getOrderByColumnReferenceStrategy() {
+ return ResultColumnReferenceStrategy.SOURCE;
+ }
+
+ /**
+ * Which strategy should be used to reference columns in the "result" when
+ * performing aggregation (i.e. when processing a group by). This is
+ * defined by ANSI SQL as the manner in which columns can be referred to in the
+ * group-by, having, and order-by clauses.
+ * <p/>
+ * The default is to use {@link ResultColumnReferenceStrategy#SOURCE} since that
+ * is the most performant.
+ *
+ * @return The strategy to use.
+ */
+ public ResultColumnReferenceStrategy getGroupByColumnReferenceStrategy() {
+ return ResultColumnReferenceStrategy.SOURCE;
+ }
+
+ /**
+ * Which strategy should be used to reference columns in the "result" when
+ * performing aggregated restirctiuon(i.e. when processing a having). This is
+ * defined by ANSI SQL as the manner in which columns can be referred to in the
+ * group-by, having, and order-by clauses.
+ * <p/>
+ * The default is to use {@link ResultColumnReferenceStrategy#SOURCE} since that
+ * is the most performant.
+ *
+ * @return The strategy to use.
+ */
+ public ResultColumnReferenceStrategy getHavingColumnReferenceStrategy() {
+ return ResultColumnReferenceStrategy.SOURCE;
+ }
}
Added: trunk/Hibernate3/src/org/hibernate/dialect/ResultColumnReferenceStrategy.java
===================================================================
--- trunk/Hibernate3/src/org/hibernate/dialect/ResultColumnReferenceStrategy.java 2006-08-04 18:25:19 UTC (rev 10220)
+++ trunk/Hibernate3/src/org/hibernate/dialect/ResultColumnReferenceStrategy.java 2006-08-04 18:37:47 UTC (rev 10221)
@@ -0,0 +1,67 @@
+package org.hibernate.dialect;
+
+import java.io.Serializable;
+import java.io.ObjectStreamException;
+import java.util.Map;
+import java.util.HashMap;
+
+/**
+ * Defines how we need to reference columns in the group-by, having, and order-by
+ * clauses.
+ *
+ * @author Steve Ebersole
+ */
+public class ResultColumnReferenceStrategy implements Serializable {
+
+ private static final Map INSTANCES = new HashMap();
+
+ /**
+ * This strategy says to reference the result columns by the qualified column name
+ * found in the result source. This strategy is not strictly allowed by ANSI SQL
+ * but is Hibernate's legacy behavior and is also the fastest of the strategies; thus
+ * it should be used if supported by the underlying database.
+ */
+ public static final ResultColumnReferenceStrategy SOURCE = new ResultColumnReferenceStrategy( "source");
+
+ /**
+ * For databases which do not support {@link #SOURCE}, ANSI SQL defines two allowable
+ * approaches. One is to reference the result column by the alias it is given in the
+ * result source (if it is given an alias). This strategy says to use this approach.
+ * <p/>
+ * The other QNSI SQL compliant approach is {@link #ORDINAL}.
+ */
+ public static final ResultColumnReferenceStrategy ALIAS = new ResultColumnReferenceStrategy( "alias" );
+
+ /**
+ * For databases which do not support {@link #SOURCE}, ANSI SQL defines two allowable
+ * approaches. One is to reference the result column by the ordinal position at which
+ * it appears in the result source. This strategy says to use this approach.
+ * <p/>
+ * The other QNSI SQL compliant approach is {@link #ALIAS}.
+ */
+ public static final ResultColumnReferenceStrategy ORDINAL = new ResultColumnReferenceStrategy( "ordinal" );
+
+ static {
+ ResultColumnReferenceStrategy.INSTANCES.put( ResultColumnReferenceStrategy.SOURCE.name, ResultColumnReferenceStrategy.SOURCE );
+ ResultColumnReferenceStrategy.INSTANCES.put( ResultColumnReferenceStrategy.ALIAS.name, ResultColumnReferenceStrategy.ALIAS );
+ ResultColumnReferenceStrategy.INSTANCES.put( ResultColumnReferenceStrategy.ORDINAL.name, ResultColumnReferenceStrategy.ORDINAL );
+ }
+
+ private final String name;
+
+ public ResultColumnReferenceStrategy(String name) {
+ this.name = name;
+ }
+
+ public String toString() {
+ return name;
+ }
+
+ private Object readResolve() throws ObjectStreamException {
+ return parse( name );
+ }
+
+ public static ResultColumnReferenceStrategy parse(String name) {
+ return ( ResultColumnReferenceStrategy ) ResultColumnReferenceStrategy.INSTANCES.get( name );
+ }
+}
Deleted: trunk/Hibernate3/src/org/hibernate/dialect/function/AnsiTrimEmulationFunction.java
===================================================================
--- trunk/Hibernate3/src/org/hibernate/dialect/function/AnsiTrimEmulationFunction.java 2006-08-04 18:25:19 UTC (rev 10220)
+++ trunk/Hibernate3/src/org/hibernate/dialect/function/AnsiTrimEmulationFunction.java 2006-08-04 18:37:47 UTC (rev 10221)
@@ -1,146 +0,0 @@
-package org.hibernate.dialect.function;
-
-import org.hibernate.Hibernate;
-import org.hibernate.QueryException;
-import org.hibernate.engine.Mapping;
-import org.hibernate.engine.SessionFactoryImplementor;
-import org.hibernate.type.Type;
-
-import java.util.List;
-import java.util.ArrayList;
-
-/**
- * A {@link SQLFunction} implementation that emulates the ANSI SQL trim function
- * on dialects which do not support the full definition. However, this function
- * definition does assume the availability of ltrim, rtrim, and replace functions
- * which it uses in various combinations to emulate the desired ANSI trim()
- * functionality.
- *
- * @author Steve Ebersole
- */
-public class AnsiTrimEmulationFunction implements SQLFunction {
-
- private static final SQLFunction LEADING_SPACE_TRIM = new SQLFunctionTemplate( Hibernate.STRING, "ltrim( ?1 )");
- private static final SQLFunction TRAILING_SPACE_TRIM = new SQLFunctionTemplate( Hibernate.STRING, "rtrim( ?1 )");
- private static final SQLFunction BOTH_SPACE_TRIM = new SQLFunctionTemplate( Hibernate.STRING, "ltrim( rtrim( ?1 ) )");
- private static final SQLFunction BOTH_SPACE_TRIM_FROM = new SQLFunctionTemplate( Hibernate.STRING, "ltrim( rtrim( ?2 ) )");
-
- private static final SQLFunction LEADING_TRIM = new SQLFunctionTemplate( Hibernate.STRING, "replace( replace( rtrim( replace( replace( ?1, ' ', '${space}$' ), ?2, ' ' ) ), ' ', ?2 ), '${space}$', ' ' )" );
- private static final SQLFunction TRAILING_TRIM = new SQLFunctionTemplate( Hibernate.STRING, "replace( replace( ltrim( replace( replace( ?1, ' ', '${space}$' ), ?2, ' ' ) ), ' ', ?2 ), '${space}$', ' ' )" );
- private static final SQLFunction BOTH_TRIM = new SQLFunctionTemplate( Hibernate.STRING, "replace( replace( ltrim( rtrim( replace( replace( ?1, ' ', '${space}$' ), ?2, ' ' ) ) ), ' ', ?2 ), '${space}$', ' ' )" );
-
- public Type getReturnType(Type columnType, Mapping mapping) throws QueryException {
- return Hibernate.STRING;
- }
-
- public boolean hasArguments() {
- return true;
- }
-
- public boolean hasParenthesesIfNoArguments() {
- return false;
- }
-
- public String render(List args, SessionFactoryImplementor factory) throws QueryException {
- // according to both the ANSI-SQL and EJB3 specs, trim can either take
- // exactly one parameter or a variable number of parameters between 1 and 4.
- // from the SQL spec:
- //
- // <trim function> ::=
- // TRIM <left paren> <trim operands> <right paren>
- //
- // <trim operands> ::=
- // [ [ <trim specification> ] [ <trim character> ] FROM ] <trim source>
- //
- // <trim specification> ::=
- // LEADING
- // | TRAILING
- // | BOTH
- //
- // If only <trim specification> is omitted, BOTH is assumed;
- // if <trim character> is omitted, space is assumed
- if ( args.size() == 1 ) {
- // we have the form: trim(trimSource)
- // so we trim leading and trailing spaces
- return BOTH_SPACE_TRIM.render( args, factory );
- }
- else if ( "from".equalsIgnoreCase( ( String ) args.get( 0 ) ) ) {
- // we have the form: trim(from trimSource).
- // This is functionally equivalent to trim(trimSource)
- return BOTH_SPACE_TRIM_FROM.render( args, factory );
- }
- else {
- // otherwise, a trim-specification and/or a trim-character
- // have been specified; we need to decide which options
- // are present and "do the right thing"
- boolean leading = true; // should leading trim-characters be trimmed?
- boolean trailing = true; // should trailing trim-characters be trimmed?
- String trimCharacter = null; // the trim-character
- String trimSource = null; // the trim-source
-
- // potentialTrimCharacterArgIndex = 1 assumes that a
- // trim-specification has been specified. we handle the
- // exception to that explicitly
- int potentialTrimCharacterArgIndex = 1;
- String firstArg = ( String ) args.get( 0 );
- if ( "leading".equalsIgnoreCase( firstArg ) ) {
- trailing = false;
- }
- else if ( "trailing".equalsIgnoreCase( firstArg ) ) {
- leading = false;
- }
- else if ( "both".equalsIgnoreCase( firstArg ) ) {
- }
- else {
- potentialTrimCharacterArgIndex = 0;
- }
-
- String potentialTrimCharacter = ( String ) args.get( potentialTrimCharacterArgIndex );
- if ( "from".equalsIgnoreCase( potentialTrimCharacter ) ) {
- trimCharacter = "' '";
- trimSource = ( String ) args.get( potentialTrimCharacterArgIndex + 1 );
- }
- else if ( potentialTrimCharacterArgIndex + 1 >= args.size() ) {
- trimCharacter = "' '";
- trimSource = potentialTrimCharacter;
- }
- else {
- trimCharacter = potentialTrimCharacter;
- if ( "from".equalsIgnoreCase( ( String ) args.get( potentialTrimCharacterArgIndex + 1 ) ) ) {
- trimSource = ( String ) args.get( potentialTrimCharacterArgIndex + 2 );
- }
- else {
- trimSource = ( String ) args.get( potentialTrimCharacterArgIndex + 1 );
- }
- }
-
- List argsToUse = null;
- argsToUse = new ArrayList();
- argsToUse.add( trimSource );
- argsToUse.add( trimCharacter );
-
- if ( trimCharacter.equals( "' '" ) ) {
- if ( leading && trailing ) {
- return BOTH_SPACE_TRIM.render( argsToUse, factory );
- }
- else if ( leading ) {
- return LEADING_SPACE_TRIM.render( argsToUse, factory );
- }
- else {
- return TRAILING_SPACE_TRIM.render( argsToUse, factory );
- }
- }
- else {
- if ( leading && trailing ) {
- return BOTH_TRIM.render( argsToUse, factory );
- }
- else if ( leading ) {
- return LEADING_TRIM.render( argsToUse, factory );
- }
- else {
- return TRAILING_TRIM.render( argsToUse, factory );
- }
- }
- }
- }
-}
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