HHH-11452 Extended audit query API to specify the use of scalar

functions.

hibernate-envers/src/main/java/org/hibernate/envers/internal/tools/query/Parameters.java

@@ -11,8 +11,10 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
+import org.hibernate.envers.configuration.Configuration;
 import org.hibernate.envers.internal.tools.MutableBoolean;
 import org.hibernate.envers.internal.tools.MutableInteger;
+import org.hibernate.envers.query.criteria.AuditFunction;
 
 /**
  * Parameters of a query, built using {@link QueryBuilder}.
@@ -311,6 +313,96 @@ public class Parameters {
 		}
 	}
 
+	/**
+	 * Add where clause with a function call on the left and a scalar value on the right.
+	 *
+	 * @param configuration the configuration.
+	 * @param function the function.
+	 * @param op the operator.
+	 * @param value the scalar value.
+	 */
+	public void addWhereWithFunction(Configuration configuration, AuditFunction function, String op, Object value) {
+		final StringBuilder expression = new StringBuilder();
+
+		QueryBuilder.appendFunctionArgument( configuration, queryParamCounter, localQueryParamValues, alias, expression, function );
+
+		expression.append( ' ' ).append( op );
+
+		String queryParam = generateQueryParam();
+		localQueryParamValues.put( queryParam, value );
+		expression.append( ' ' ).append( ':' ).append( queryParam );
+
+		expressions.add( expression.toString() );
+	}
+
+	/**
+	 * Add a where clause with a function call on the left and an optionally aliased property on the right.
+	 *
+	 * @param configuration the configuration.
+	 * @param function the function.
+	 * @param op the operator.
+	 * @param aliasRight the optional alias of the right property, may be {@literal null}
+	 * @param right the property.
+	 */
+	public void addWhereWithFunction(Configuration configuration, AuditFunction function, String op, String aliasRight, String right) {
+		final StringBuilder expression = new StringBuilder();
+
+		QueryBuilder.appendFunctionArgument( configuration, queryParamCounter, localQueryParamValues, alias, expression, function );
+
+		expression.append( ' ' ).append( op ).append( ' ' );
+
+		if ( aliasRight != null ) {
+			expression.append( aliasRight ).append( '.' );
+		}
+		expression.append( right );
+
+		expressions.add( expression.toString() );
+	}
+
+	/**
+	 * Adds a where clause with a left (optionally aliased) property and a function call on the right side.
+	 *
+	 * @param configuration the configuration.
+	 * @param aliasLeft the optional alias of the left property, may be {@literal null}
+	 * @param left the property.
+	 * @param op the operator.
+	 * @param function the function.
+	 */
+	public void addWhereWithFunction(Configuration configuration, String aliasLeft, String left, String op, AuditFunction function) {
+		final StringBuilder expression = new StringBuilder();
+
+		if ( aliasLeft != null ) {
+			expression.append( aliasLeft ).append( '.' );
+		}
+		expression.append( left );
+
+		expression.append( ' ' ).append( op ).append( ' ' );
+
+		QueryBuilder.appendFunctionArgument( configuration, queryParamCounter, localQueryParamValues, alias, expression, function );
+
+		expressions.add( expression.toString() );
+	}
+
+	/**
+	 * Adds a where clause with a function call on both the left and right of the predicate.
+	 *
+	 * @param configuration the configuration.
+	 * @param left the left-side function.
+	 * @param op the operator.
+	 * @param right the right-side function.
+	 */
+	public void addWhereWithFunction(Configuration configuration, AuditFunction left, String op, AuditFunction right) {
+		final StringBuilder expression = new StringBuilder();
+
+		QueryBuilder.appendFunctionArgument( configuration, queryParamCounter, localQueryParamValues, alias, expression, left );
+
+		expression.append( ' ' ).append( op ).append( ' ' );
+
+		QueryBuilder.appendFunctionArgument( configuration, queryParamCounter, localQueryParamValues, alias, expression, right );
+
+		expressions.add( expression.toString() );
+	}
+
 	private void append(StringBuilder sb, String toAppend, MutableBoolean isFirst) {
 		if ( !isFirst.isSet() ) {
 			sb.append( " " ).append( connective ).append( " " );

hibernate-envers/src/main/java/org/hibernate/envers/internal/tools/query/QueryBuilder.java

@@ -17,11 +17,14 @@ import jakarta.persistence.criteria.JoinType;
 import org.hibernate.Session;
 import org.hibernate.engine.spi.SessionFactoryImplementor;
 import org.hibernate.envers.RevisionType;
+import org.hibernate.envers.configuration.Configuration;
 import org.hibernate.envers.function.OrderByFragmentFunction;
 import org.hibernate.envers.internal.entities.RevisionTypeType;
 import org.hibernate.envers.internal.tools.MutableInteger;
 import org.hibernate.envers.internal.tools.StringTools;
 import org.hibernate.envers.internal.tools.Triple;
+import org.hibernate.envers.query.criteria.AuditFunction;
+import org.hibernate.envers.query.criteria.AuditProperty;
 import org.hibernate.envers.tools.Pair;
 import org.hibernate.query.Query;
 import org.hibernate.query.internal.QueryLiteralHelper;
@@ -62,6 +65,10 @@ public class QueryBuilder {
 	 * A list of complete projection definitions: either a sole property name, or a function(property name).
 	 */
 	private final List<String> projections;
+	/**
+	 * Values of parameters used in projections.
+	 */
+	private final Map<String, Object> projectionQueryParamValues;
 
 	private final List<Pair<String, String>> orderFragments;
 
@@ -100,6 +107,7 @@ public class QueryBuilder {
 		froms = new ArrayList<>();
 		orders = new ArrayList<>();
 		projections = new ArrayList<>();
+		projectionQueryParamValues = new HashMap<>();
 		orderFragments = new ArrayList<>();
 
 		addFrom( entityName, alias, true );
@@ -120,6 +128,7 @@ public class QueryBuilder {
 		froms = new ArrayList<>( other.froms );
 		orders = new ArrayList<>( other.orders );
 		projections = new ArrayList<>( other.projections );
+		projectionQueryParamValues = new HashMap<>( other.projectionQueryParamValues );
 		orderFragments = new ArrayList<>( other.orderFragments );
 	}
 
@@ -205,6 +214,48 @@ public class QueryBuilder {
 		}
 	}
 
+	public void addProjection(Configuration configuration, AuditFunction function) {
+		final StringBuilder expression = new StringBuilder();
+		appendFunctionArgument( configuration, paramCounter, projectionQueryParamValues, alias, expression, function );
+		projections.add( expression.toString() );
+	}
+
+	protected static void appendFunctionArgument(
+			Configuration configuration,
+			MutableInteger paramCounter,
+			Map<String, Object> queryParamValues,
+			String alias,
+			StringBuilder expression,
+			Object argument) {
+		if ( argument instanceof AuditFunction ) {
+			AuditFunction function = (AuditFunction) argument;
+			expression.append( function.getFunction() ).append( '(' );
+			boolean first = true;
+			for ( final Object innerArg : function.getArguments() ) {
+				if ( !first ) {
+					expression.append( ',' );
+				}
+				appendFunctionArgument( configuration, paramCounter, queryParamValues, alias, expression, innerArg );
+				first = false;
+			}
+			expression.append( ')' );
+		}
+		else if ( argument instanceof AuditProperty ) {
+			AuditProperty<?> property = (AuditProperty<?>) argument;
+			String propertyAlias = property.getAlias( alias );
+			if ( propertyAlias != null ) {
+				expression.append( propertyAlias ).append( '.' );
+			}
+			String propertyName = property.getPropertyNameGetter().get( configuration );
+			expression.append( propertyName );
+		}
+		else {
+			String queryParam = "_p" + paramCounter.getAndIncrease();
+			queryParamValues.put( queryParam, argument );
+			expression.append( ':' ).append( queryParam );
+		}
+	}
+
 	/**
 	 * Builds the given query, appending results to the given string buffer, and adding all query parameter values
 	 * that are used to the map provided.
@@ -222,6 +273,7 @@ public class QueryBuilder {
 			// all aliases separated with commas
 			StringTools.append( sb, getSelectAliasList().iterator(), ", " );
 		}
+		queryParamValues.putAll( projectionQueryParamValues );
 		sb.append( " from " );
 		// all from entities with aliases
 		boolean first = true;

hibernate-envers/src/main/java/org/hibernate/envers/query/AuditEntity.java

@@ -6,10 +6,15 @@
  */
 package org.hibernate.envers.query;
 
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
 import org.hibernate.envers.RevisionType;
 import org.hibernate.envers.query.criteria.AuditConjunction;
 import org.hibernate.envers.query.criteria.AuditCriterion;
 import org.hibernate.envers.query.criteria.AuditDisjunction;
+import org.hibernate.envers.query.criteria.AuditFunction;
 import org.hibernate.envers.query.criteria.AuditId;
 import org.hibernate.envers.query.criteria.AuditProperty;
 import org.hibernate.envers.query.criteria.AuditRelatedId;
@@ -176,4 +181,30 @@ public class AuditEntity {
 	public static AuditProjection selectEntity(boolean distinct) {
 		return new EntityAuditProjection( null, distinct );
 	}
+
+	/**
+	 * Create restrictions or projections using a function.
+	 * <p>
+	 * Examples:
+	 * <ul>
+	 * 		<li>AuditEntity.function("upper", AuditEntity.property("prop"))</li>
+	 * 		<li>AuditEntity.function("substring", AuditEntity.property("prop"), 3, 2)</li>
+	 * 		<li>AuditEntity.function("concat", AuditEntity.function("upper", AuditEntity.property("prop1")),
+	 * 				AuditEntity.function("substring", AuditEntity.property("prop2"), 1, 2))</li>
+	 * </ul>
+	 * 
+	 * @param function the name of the function
+	 * @param arguments the arguments of the function. A function argument can either be
+	 * <ul>
+	 * 		<li>a primitive value like a Number or a String</li>
+	 * 		<li>an AuditProperty (see {@link #property(String)})</li>
+	 * 		<li>an other AuditFunction</li>
+	 * </ul>
+	 * @return
+	 */
+	public static AuditFunction function(final String function, final Object... arguments) {
+		List<Object> argumentList = new ArrayList<>();
+		Collections.addAll( argumentList, arguments );
+		return new AuditFunction( function, argumentList );
+	}
 }

hibernate-envers/src/main/java/org/hibernate/envers/query/criteria/AuditFunction.java

@@ -0,0 +1,241 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.envers.query.criteria;
+
+import java.util.List;
+import java.util.Map;
+
+import org.hibernate.envers.boot.internal.EnversService;
+import org.hibernate.envers.internal.entities.EntityInstantiator;
+import org.hibernate.envers.internal.reader.AuditReaderImplementor;
+import org.hibernate.envers.internal.tools.query.QueryBuilder;
+import org.hibernate.envers.query.criteria.internal.FunctionFunctionAuditExpression;
+import org.hibernate.envers.query.criteria.internal.PropertyFunctionAuditExpression;
+import org.hibernate.envers.query.criteria.internal.SimpleFunctionAuditExpression;
+import org.hibernate.envers.query.projection.AuditProjection;
+
+/**
+ * Create restrictions or projections using a function.
+ * 
+ * @author Felix Feisst (feisst dot felix at gmail dot com)
+ */
+public class AuditFunction implements AuditProjection {
+
+	private final String function;
+	private final List<Object> arguments;
+
+	public AuditFunction(String function, List<Object> arguments) {
+		this.function = function;
+		this.arguments = arguments;
+	}
+
+	public String getFunction() {
+		return function;
+	}
+
+	public List<Object> getArguments() {
+		return arguments;
+	}
+
+	/**
+	 * Apply an "equal" constraint
+	 */
+	public AuditCriterion eq(Object value) {
+		return new SimpleFunctionAuditExpression( this, value, "=" );
+	}
+
+	/**
+	 * Apply a "not equal" constraint
+	 */
+	public AuditCriterion ne(Object value) {
+		return new SimpleFunctionAuditExpression( this, value, "<>" );
+	}
+
+	/**
+	 * Apply a "greater than" constraint
+	 */
+	public AuditCriterion gt(Object value) {
+		return new SimpleFunctionAuditExpression( this, value, ">" );
+	}
+
+	/**
+	 * Apply a "less than" constraint
+	 */
+	public AuditCriterion lt(Object value) {
+		return new SimpleFunctionAuditExpression( this, value, "<" );
+	}
+
+	/**
+	 * Apply a "less than or equal" constraint
+	 */
+	public AuditCriterion le(Object value) {
+		return new SimpleFunctionAuditExpression( this, value, "<=" );
+	}
+
+	/**
+	 * Apply a "greater than or equal" constraint
+	 */
+	public AuditCriterion ge(Object value) {
+		return new SimpleFunctionAuditExpression( this, value, ">=" );
+	}
+
+	/**
+	 * Apply an "equal" constraint to a property
+	 */
+	public AuditCriterion eqProperty(String propertyName) {
+		return eqProperty( null, propertyName );
+	}
+
+	/**
+	 * Apply an "equal" constraint to a property
+	 *
+	 * @param alias the alias of the entity which owns the property.
+	 */
+	public AuditCriterion eqProperty(String alias, String propertyName) {
+		return new PropertyFunctionAuditExpression( this, alias, propertyName, "=" );
+	}
+
+	/**
+	 * Apply a "not equal" constraint to a property
+	 */
+	public AuditCriterion neProperty(String propertyName) {
+		return neProperty( null, propertyName );
+	}
+
+	/**
+	 * Apply a "not equal" constraint to a property
+	 *
+	 * @param alias the alias of the entity which owns the property.
+	 */
+	public AuditCriterion neProperty(String alias, String propertyName) {
+		return new PropertyFunctionAuditExpression( this, alias, propertyName, "<>" );
+	}
+
+	/**
+	 * Apply a "less than" constraint to a property
+	 */
+	public AuditCriterion ltProperty(String propertyName) {
+		return ltProperty( null, propertyName );
+	}
+
+	/**
+	 * Apply a "less than" constraint to a property
+	 *
+	 * @param alias the alias of the entity which owns the property.
+	 */
+	public AuditCriterion ltProperty(String alias, String propertyName) {
+		return new PropertyFunctionAuditExpression( this, alias, propertyName, "<" );
+	}
+
+	/**
+	 * Apply a "less than or equal" constraint to a property
+	 */
+	public AuditCriterion leProperty(String propertyName) {
+		return leProperty( null, propertyName );
+	}
+
+	/**
+	 * Apply a "less than or equal" constraint to a property
+	 *
+	 * @param alias the alias of the entity which owns the property.
+	 */
+	public AuditCriterion leProperty(String alias, String propertyName) {
+		return new PropertyFunctionAuditExpression( this, alias, propertyName, "<=" );
+	}
+
+	/**
+	 * Apply a "greater than" constraint to a property
+	 */
+	public AuditCriterion gtProperty(String propertyName) {
+		return gtProperty( null, propertyName );
+	}
+
+	/**
+	 * Apply a "greater than" constraint to a property
+	 *
+	 * @param alias the alias of the entity which owns the property.
+	 */
+	public AuditCriterion gtProperty(String alias, String propertyName) {
+		return new PropertyFunctionAuditExpression( this, alias, propertyName, ">" );
+	}
+
+	/**
+	 * Apply a "greater than or equal" constraint to a property
+	 */
+	public AuditCriterion geProperty(String propertyName) {
+		return geProperty( null, propertyName );
+	}
+
+	/**
+	 * Apply a "greater than or equal" constraint to a property
+	 *
+	 * @param alias the alias of the entity which owns the property.
+	 */
+	public AuditCriterion geProperty(String alias, String propertyName) {
+		return new PropertyFunctionAuditExpression( this, alias, propertyName, ">=" );
+	}
+
+	/**
+	 * Apply an "equal" constraint to another function
+	 */
+	public AuditCriterion eqFunction(AuditFunction otherFunction) {
+		return new FunctionFunctionAuditExpression( this, otherFunction, "=" );
+	}
+
+	/**
+	 * Apply a "not equal" constraint to another function
+	 */
+	public AuditCriterion neFunction(AuditFunction otherFunction) {
+		return new FunctionFunctionAuditExpression( this, otherFunction, "<>" );
+	}
+
+	/**
+	 * Apply a "less than" constraint to another function
+	 */
+	public AuditCriterion ltFunction(AuditFunction otherFunction) {
+		return new FunctionFunctionAuditExpression( this, otherFunction, "<" );
+	}
+
+	/**
+	 * Apply a "less than or equal" constraint to another function
+	 */
+	public AuditCriterion leFunction(AuditFunction otherFunction) {
+		return new FunctionFunctionAuditExpression( this, otherFunction, "<=" );
+	}
+
+	/**
+	 * Apply a "greater than" constraint to another function
+	 */
+	public AuditCriterion gtFunction(AuditFunction otherFunction) {
+		return new FunctionFunctionAuditExpression( this, otherFunction, ">" );
+	}
+
+	/**
+	 * Apply a "greater than or equal" constraint to another function
+	 */
+	public AuditCriterion geFunction(AuditFunction otherFunction) {
+		return new FunctionFunctionAuditExpression( this, otherFunction, ">=" );
+	}
+
+	@Override
+	public void addProjectionToQuery(EnversService enversService, AuditReaderImplementor auditReader,
+			Map<String, String> aliasToEntityNameMap, String baseAlias, QueryBuilder queryBuilder) {
+		queryBuilder.addProjection( enversService.getConfig(), this );
+	}
+
+	@Override
+	public Object convertQueryResult(EnversService enversService, EntityInstantiator entityInstantiator,
+			String entityName, Number revision, Object value) {
+		return value;
+	}
+
+	@Override
+	public String getAlias(String baseAlias) {
+		return baseAlias;
+	}
+
+}

hibernate-envers/src/main/java/org/hibernate/envers/query/criteria/AuditProperty.java

@@ -7,11 +7,15 @@
 package org.hibernate.envers.query.criteria;
 
 import java.util.Collection;
+import java.util.Map;
 
 import org.hibernate.envers.boot.internal.EnversService;
-import org.hibernate.envers.configuration.Configuration;
 import org.hibernate.envers.internal.entities.EntityInstantiator;
+import org.hibernate.envers.internal.reader.AuditReaderImplementor;
+import org.hibernate.envers.internal.tools.query.QueryBuilder;
 import org.hibernate.envers.query.criteria.internal.BetweenAuditExpression;
+import org.hibernate.envers.query.criteria.internal.CriteriaTools;
+import org.hibernate.envers.query.criteria.internal.FunctionPropertyAuditExpression;
 import org.hibernate.envers.query.criteria.internal.IlikeAuditExpression;
 import org.hibernate.envers.query.criteria.internal.InAuditExpression;
 import org.hibernate.envers.query.criteria.internal.NotNullAuditExpression;
@@ -42,6 +46,15 @@ public class AuditProperty<T> implements AuditProjection {
 		this.propertyNameGetter = propertyNameGetter;
 	}
 
+	@Override
+	public String getAlias(String baseAlias) {
+		return alias == null ? baseAlias : alias;
+	}
+
+	public PropertyNameGetter getPropertyNameGetter() {
+		return propertyNameGetter;
+	}
+
 	public AuditCriterion hasChanged() {
 		return new SimpleAuditExpression( alias, new ModifiedFlagPropertyName( propertyNameGetter ), true, "=" );
 	}
@@ -280,6 +293,48 @@ public class AuditProperty<T> implements AuditProjection {
 		return new PropertyAuditExpression( alias, propertyNameGetter, otherAlias, otherPropertyName, ">=" );
 	}
 
+	/**
+	 * Apply an "equal" constraint to a function
+	 */
+	public AuditCriterion eqFunction(AuditFunction otherFunction) {
+		return new FunctionPropertyAuditExpression( alias, propertyNameGetter, otherFunction, "=" );
+	}
+
+	/**
+	 * Apply a "not equal" constraint to a function
+	 */
+	public AuditCriterion neFunction(AuditFunction otherFunction) {
+		return new FunctionPropertyAuditExpression( alias, propertyNameGetter, otherFunction, "<>" );
+	}
+
+	/**
+	 * Apply a "less than" constraint to a function
+	 */
+	public AuditCriterion ltFunction(AuditFunction otherFunction) {
+		return new FunctionPropertyAuditExpression( alias, propertyNameGetter, otherFunction, "<" );
+	}
+
+	/**
+	 * Apply a "less than or equal" constraint to a function
+	 */
+	public AuditCriterion leFunction(AuditFunction otherFunction) {
+		return new FunctionPropertyAuditExpression( alias, propertyNameGetter, otherFunction, "<=" );
+	}
+
+	/**
+	 * Apply a "greater than" constraint to a function
+	 */
+	public AuditCriterion gtFunction(AuditFunction otherFunction) {
+		return new FunctionPropertyAuditExpression( alias, propertyNameGetter, otherFunction, ">" );
+	}
+
+	/**
+	 * Apply a "greater than or equal" constraint to a function
+	 */
+	public AuditCriterion geFunction(AuditFunction otherFunction) {
+		return new FunctionPropertyAuditExpression( alias, propertyNameGetter, otherFunction, ">=" );
+	}
+
 	/**
 	 * Apply an "is not null" constraint to the another property
 	 */
@@ -349,16 +404,21 @@ public class AuditProperty<T> implements AuditProjection {
 
 	// Projection on this property
 
-	/**
+	@Override
-	 * @deprecated since 6.0, use {@link #getData(Configuration)} instead.
+	public void addProjectionToQuery(EnversService enversService, AuditReaderImplementor auditReader,
-	 */
+			Map<String, String> aliasToEntityNameMap, String baseAlias, QueryBuilder queryBuilder) {
-	@Deprecated
+		String projectionEntityAlias = getAlias( baseAlias );
-	public ProjectionData getData(EnversService enversService) {
+		String projectionEntityName = aliasToEntityNameMap.get( projectionEntityAlias );
-		return new ProjectionData( null, alias, propertyNameGetter.get( enversService.getConfig() ), false );
+		String propertyName = CriteriaTools.determinePropertyName(
-	}
+				enversService,
-
+				auditReader,
-	public ProjectionData getData(Configuration configuration) {
+				projectionEntityName,
-		return new ProjectionData( null, alias, propertyNameGetter.get( configuration ), false );
+				propertyNameGetter );
+		queryBuilder.addProjection(
+				null,
+				projectionEntityAlias,
+				propertyName,
+				false );
 	}
 
 	// Order

hibernate-envers/src/main/java/org/hibernate/envers/query/criteria/internal/FunctionFunctionAuditExpression.java

@@ -0,0 +1,48 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.envers.query.criteria.internal;
+
+import java.util.Map;
+
+import org.hibernate.envers.boot.internal.EnversService;
+import org.hibernate.envers.internal.reader.AuditReaderImplementor;
+import org.hibernate.envers.internal.tools.query.Parameters;
+import org.hibernate.envers.internal.tools.query.QueryBuilder;
+import org.hibernate.envers.query.criteria.AuditCriterion;
+import org.hibernate.envers.query.criteria.AuditFunction;
+
+/**
+ * An audit query criterion that defines a predicate where both sides are a function.
+ *
+ * @author Felix Feisst (feisst dot felix at gmail dot com)
+ */
+public class FunctionFunctionAuditExpression implements AuditCriterion {
+
+	private AuditFunction leftFunction;
+	private AuditFunction rightFunction;
+	private String op;
+
+	public FunctionFunctionAuditExpression(
+			AuditFunction leftFunction,
+			AuditFunction rightFunction,
+			String op) {
+		this.leftFunction = leftFunction;
+		this.rightFunction = rightFunction;
+		this.op = op;
+	}
+
+	@Override
+	public void addToQuery(
+			EnversService enversService,
+			AuditReaderImplementor auditReader,
+			Map<String, String> aliasToEntityNameMap,
+			String baseAlias,
+			QueryBuilder queryBuilder,
+			Parameters parameters) {
+		parameters.addWhereWithFunction( enversService.getConfig(), leftFunction, op, rightFunction );
+	}
+}

hibernate-envers/src/main/java/org/hibernate/envers/query/criteria/internal/FunctionPropertyAuditExpression.java

@@ -0,0 +1,61 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.envers.query.criteria.internal;
+
+import java.util.Map;
+
+import org.hibernate.envers.boot.internal.EnversService;
+import org.hibernate.envers.internal.reader.AuditReaderImplementor;
+import org.hibernate.envers.internal.tools.query.Parameters;
+import org.hibernate.envers.internal.tools.query.QueryBuilder;
+import org.hibernate.envers.query.criteria.AuditCriterion;
+import org.hibernate.envers.query.criteria.AuditFunction;
+import org.hibernate.envers.query.internal.property.PropertyNameGetter;
+
+/**
+ * An audit query criterion that defines a predicate that is a comparison between a function
+ * and an audit property expression.
+ *
+ * @author Felix Feisst (feisst dot felix at gmail dot com)
+ */
+public class FunctionPropertyAuditExpression implements AuditCriterion {
+
+	private String alias;
+	private PropertyNameGetter propertyNameGetter;
+	private AuditFunction function;
+	private String op;
+
+	public FunctionPropertyAuditExpression(
+			String alias,
+			PropertyNameGetter propertyNameGetter,
+			AuditFunction function,
+			String op) {
+		this.alias = alias;
+		this.propertyNameGetter = propertyNameGetter;
+		this.function = function;
+		this.op = op;
+	}
+
+	@Override
+	public void addToQuery(
+			EnversService enversService,
+			AuditReaderImplementor auditReader,
+			Map<String, String> aliasToEntityNameMap,
+			String baseAlias,
+			QueryBuilder queryBuilder,
+			Parameters parameters) {
+		String effectiveAlias = alias == null ? baseAlias : alias;
+		String entityName = aliasToEntityNameMap.get( effectiveAlias );
+		String propertyName = CriteriaTools.determinePropertyName(
+				enversService,
+				auditReader,
+				entityName,
+				propertyNameGetter );
+		CriteriaTools.checkPropertyNotARelation( enversService, entityName, propertyName );
+		parameters.addWhereWithFunction( enversService.getConfig(), effectiveAlias, propertyName, op, function );
+	}
+}

hibernate-envers/src/main/java/org/hibernate/envers/query/criteria/internal/PropertyFunctionAuditExpression.java

@@ -0,0 +1,60 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.envers.query.criteria.internal;
+
+import java.util.Map;
+
+import org.hibernate.envers.boot.internal.EnversService;
+import org.hibernate.envers.internal.reader.AuditReaderImplementor;
+import org.hibernate.envers.internal.tools.query.Parameters;
+import org.hibernate.envers.internal.tools.query.QueryBuilder;
+import org.hibernate.envers.query.criteria.AuditCriterion;
+import org.hibernate.envers.query.criteria.AuditFunction;
+
+/**
+ * An audit query criterion where a function is compared to a property.
+ *
+ * @author Felix Feisst (feisst dot felix at gmail dot com)
+ */
+public class PropertyFunctionAuditExpression implements AuditCriterion {
+
+	private AuditFunction function;
+	private String otherAlias;
+	private String otherPropertyName;
+	private String op;
+
+	public PropertyFunctionAuditExpression(
+			AuditFunction function,
+			String otherAlias,
+			String otherPropertyName,
+			String op) {
+		this.function = function;
+		this.otherAlias = otherAlias;
+		this.otherPropertyName = otherPropertyName;
+		this.op = op;
+	}
+
+	@Override
+	public void addToQuery(
+			EnversService enversService,
+			AuditReaderImplementor auditReader,
+			Map<String, String> aliasToEntityNameMap,
+			String baseAlias,
+			QueryBuilder queryBuilder,
+			Parameters parameters) {
+		String effectiveOtherAlias = otherAlias == null ? baseAlias : otherAlias;
+		String otherEntityName = aliasToEntityNameMap.get( effectiveOtherAlias );
+		/*
+		 * Check that the other property name is not a relation. However, we can only do this for audited entities. If
+		 * the other property belongs to a non-audited entity, we have to skip this check.
+		 */
+		if ( enversService.getEntitiesConfigurations().isVersioned( otherEntityName ) ) {
+			CriteriaTools.checkPropertyNotARelation( enversService, otherEntityName, otherPropertyName );
+		}
+		parameters.addWhereWithFunction( enversService.getConfig(), function, op, effectiveOtherAlias, otherPropertyName );
+	}
+}

hibernate-envers/src/main/java/org/hibernate/envers/query/criteria/internal/SimpleFunctionAuditExpression.java

@@ -0,0 +1,41 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.envers.query.criteria.internal;
+
+import java.util.Map;
+
+import org.hibernate.envers.boot.internal.EnversService;
+import org.hibernate.envers.internal.reader.AuditReaderImplementor;
+import org.hibernate.envers.internal.tools.query.Parameters;
+import org.hibernate.envers.internal.tools.query.QueryBuilder;
+import org.hibernate.envers.query.criteria.AuditCriterion;
+import org.hibernate.envers.query.criteria.AuditFunction;
+
+/**
+ * An audit query criterion that compares a function call with a scalar value.
+ *
+ * @author Felix Feisst (feisst dot felix at gmail dot com)
+ */
+public class SimpleFunctionAuditExpression implements AuditCriterion {
+
+	private AuditFunction function;
+	private Object value;
+	private String op;
+
+	public SimpleFunctionAuditExpression(AuditFunction function, Object value, String op) {
+		this.function = function;
+		this.value = value;
+		this.op = op;
+	}
+
+	@Override
+	public void addToQuery(EnversService enversService, AuditReaderImplementor versionsReader,
+			Map<String, String> aliasToEntityNameMap, String baseAlias, QueryBuilder qb, Parameters parameters) {
+		parameters.addWhereWithFunction( enversService.getConfig(), function, op, value );
+	}
+
+}

hibernate-envers/src/main/java/org/hibernate/envers/query/internal/impl/AbstractAuditQuery.java

@@ -135,22 +135,10 @@ public abstract class AbstractAuditQuery implements AuditQueryImplementor {
 	// Projection and order
 
 	public AuditQuery addProjection(AuditProjection projection) {
-		AuditProjection.ProjectionData projectionData = projection.getData( enversService.getConfig() );
+		String projectionEntityAlias = projection.getAlias( REFERENCED_ENTITY_ALIAS );
-		String projectionEntityAlias = projectionData.getAlias( REFERENCED_ENTITY_ALIAS );
 		String projectionEntityName = aliasToEntityNameMap.get( projectionEntityAlias );
 		registerProjection( projectionEntityName, projection );
-		String propertyName = CriteriaTools.determinePropertyName(
+		projection.addProjectionToQuery( enversService, versionsReader, aliasToEntityNameMap, REFERENCED_ENTITY_ALIAS, qb );
-				enversService,
-				versionsReader,
-				projectionEntityName,
-				projectionData.getPropertyName()
-		);
-		qb.addProjection(
-				projectionData.getFunction(),
-				projectionEntityAlias,
-				propertyName,
-				projectionData.isDistinct()
-		);
 		return this;
 	}
 

hibernate-envers/src/main/java/org/hibernate/envers/query/internal/impl/AuditAssociationQueryImpl.java

@@ -159,22 +159,10 @@ public class AuditAssociationQueryImpl<Q extends AuditQueryImplementor>
 
 	@Override
 	public AuditAssociationQueryImpl<Q> addProjection(AuditProjection projection) {
-		AuditProjection.ProjectionData projectionData = projection.getData( enversService.getConfig() );
+		String projectionEntityAlias = projection.getAlias( alias );
-		String projectionEntityAlias = projectionData.getAlias( alias );
 		String projectionEntityName = aliasToEntityNameMap.get( projectionEntityAlias );
-		String propertyName = CriteriaTools.determinePropertyName(
-				enversService,
-				auditReader,
-				projectionEntityName,
-				projectionData.getPropertyName()
-		);
-		queryBuilder.addProjection(
-				projectionData.getFunction(),
-				projectionEntityAlias,
-				propertyName,
-				projectionData.isDistinct()
-		);
 		registerProjection( projectionEntityName, projection );
+		projection.addProjectionToQuery( enversService, auditReader, aliasToEntityNameMap, alias, queryBuilder );
 		return this;
 	}
 

hibernate-envers/src/main/java/org/hibernate/envers/query/projection/AuditProjection.java

@@ -6,9 +6,12 @@
  */
 package org.hibernate.envers.query.projection;
 
+import java.util.Map;
+
 import org.hibernate.envers.boot.internal.EnversService;
-import org.hibernate.envers.configuration.Configuration;
 import org.hibernate.envers.internal.entities.EntityInstantiator;
+import org.hibernate.envers.internal.reader.AuditReaderImplementor;
+import org.hibernate.envers.internal.tools.query.QueryBuilder;
 
 /**
  * @author Adam Warski (adam at warski dot org)
@@ -17,10 +20,28 @@ import org.hibernate.envers.internal.entities.EntityInstantiator;
 public interface AuditProjection {
 
 	/**
-	 * @param configuration the configuration
+	 * Adds an audit projection to the specified query.
-	 * @return get the project data
+	 *
+	 * @param enversService the Envers service
+	 * @param auditReader the audit reader implementor
+	 * @param aliasToEntityNameMap the entity name alias map
+	 * @param baseAlias the base alias, if one is specified; may be {@literal null}
+	 * @param queryBuilder the query builder
 	 */
-	ProjectionData getData(Configuration configuration);
+	void addProjectionToQuery(
+			EnversService enversService,
+			AuditReaderImplementor auditReader,
+			Map<String, String> aliasToEntityNameMap,
+			String baseAlias,
+			QueryBuilder queryBuilder);
+
+	/**
+	 * Get the alias associated with the audit projection.
+	 *
+	 * @param baseAlias the base alias if one exists; may be {@literal null}
+	 * @return the alias
+	 */
+	String getAlias(String baseAlias);
 
 	/**
 	 * @param enversService the Envers service
@@ -38,35 +59,4 @@ public interface AuditProjection {
 			final Object value
 	);
 
-	class ProjectionData {
-
-		private final String function;
-		private final String alias;
-		private final String propertyName;
-		private final boolean distinct;
-
-		public ProjectionData(String function, String alias, String propertyName, boolean distinct) {
-			this.function = function;
-			this.alias = alias;
-			this.propertyName = propertyName;
-			this.distinct = distinct;
-		}
-
-		public String getFunction() {
-			return function;
-		}
-
-		public String getAlias(String baseAlias) {
-			return alias == null ? baseAlias : alias;
-		}
-
-		public String getPropertyName() {
-			return propertyName;
-		}
-
-		public boolean isDistinct() {
-			return distinct;
-		}
-
-	}
 }

hibernate-envers/src/main/java/org/hibernate/envers/query/projection/internal/EntityAuditProjection.java

@@ -9,8 +9,9 @@ package org.hibernate.envers.query.projection.internal;
 import java.util.Map;
 
 import org.hibernate.envers.boot.internal.EnversService;
-import org.hibernate.envers.configuration.Configuration;
 import org.hibernate.envers.internal.entities.EntityInstantiator;
+import org.hibernate.envers.internal.reader.AuditReaderImplementor;
+import org.hibernate.envers.internal.tools.query.QueryBuilder;
 import org.hibernate.envers.query.projection.AuditProjection;
 
 /**
@@ -28,9 +29,19 @@ public class EntityAuditProjection implements AuditProjection {
 	}
 
 	@Override
-	public ProjectionData getData(Configuration configuration) {
+	public String getAlias(String baseAlias) {
-		// no property is selected, instead the whole entity (alias) is selected
+		return alias == null ? baseAlias : alias;
-		return new ProjectionData( null, alias, null, distinct );
+	}
+
+	@Override
+	public void addProjectionToQuery(EnversService enversService, AuditReaderImplementor auditReader,
+			Map<String, String> aliasToEntityNameMap, String baseAlias, QueryBuilder queryBuilder) {
+		String projectionEntityAlias = getAlias( baseAlias );
+		queryBuilder.addProjection(
+				null,
+				projectionEntityAlias,
+				null,
+				distinct );
 	}
 
 	@Override

hibernate-envers/src/main/java/org/hibernate/envers/query/projection/internal/PropertyAuditProjection.java

@@ -6,9 +6,13 @@
  */
 package org.hibernate.envers.query.projection.internal;
 
+import java.util.Map;
+
 import org.hibernate.envers.boot.internal.EnversService;
-import org.hibernate.envers.configuration.Configuration;
 import org.hibernate.envers.internal.entities.EntityInstantiator;
+import org.hibernate.envers.internal.reader.AuditReaderImplementor;
+import org.hibernate.envers.internal.tools.query.QueryBuilder;
+import org.hibernate.envers.query.criteria.internal.CriteriaTools;
 import org.hibernate.envers.query.internal.property.PropertyNameGetter;
 import org.hibernate.envers.query.projection.AuditProjection;
 
@@ -30,10 +34,29 @@ public class PropertyAuditProjection implements AuditProjection {
 	}
 
 	@Override
-	public ProjectionData getData(Configuration configuration) {
+	public String getAlias(String baseAlias) {
-		String propertyName = propertyNameGetter.get( configuration );
+		return alias == null ? baseAlias : alias;
-		
+	}
-		return new ProjectionData( function, alias, propertyName, distinct );
+
+	@Override
+	public void addProjectionToQuery(
+			EnversService enversService,
+			AuditReaderImplementor auditReader,
+			Map<String, String> aliasToEntityNameMap,
+			String baseAlias,
+			QueryBuilder queryBuilder) {
+		String projectionEntityAlias = getAlias( baseAlias );
+		String projectionEntityName = aliasToEntityNameMap.get( projectionEntityAlias );
+		String propertyName = CriteriaTools.determinePropertyName(
+				enversService,
+				auditReader,
+				projectionEntityName,
+				propertyNameGetter );
+		queryBuilder.addProjection(
+				function,
+				projectionEntityAlias,
+				propertyName,
+				distinct );
 	}
 
 	@Override

hibernate-envers/src/test/java/org/hibernate/envers/test/integration/query/AuditFunctionQueryTest.java

@@ -0,0 +1,156 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.envers.test.integration.query;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.EntityManager;
+import jakarta.persistence.Id;
+
+import org.hibernate.envers.Audited;
+import org.hibernate.envers.query.AuditEntity;
+import org.hibernate.orm.test.envers.BaseEnversJPAFunctionalTestCase;
+import org.hibernate.orm.test.envers.Priority;
+import org.junit.Test;
+
+/**
+ * @author Felix Feisst (feisst dot felix at gmail dot com)
+ */
+public class AuditFunctionQueryTest extends BaseEnversJPAFunctionalTestCase {
+
+	@Entity
+	@Audited
+	public static class TestEntity {
+
+		@Id
+		private Long id;
+		private String string1;
+		private String string2;
+		private Integer int1;
+
+		public Long getId() {
+			return id;
+		}
+
+		public void setId(Long id) {
+			this.id = id;
+		}
+
+		public String getString1() {
+			return string1;
+		}
+
+		public void setString1(String string1) {
+			this.string1 = string1;
+		}
+
+		public String getString2() {
+			return string2;
+		}
+
+		public Integer getInt1() {
+			return int1;
+		}
+
+		public void setInt1(Integer int1) {
+			this.int1 = int1;
+		}
+
+		public void setString2(String string2) {
+			this.string2 = string2;
+		}
+
+	}
+
+	private TestEntity testEntity1;
+
+	@Override
+	protected Class<?>[] getAnnotatedClasses() {
+		return new Class<?>[]{ TestEntity.class };
+	}
+
+	@Test
+	@Priority(10)
+	public void initData() {
+		EntityManager em = getEntityManager();
+		em.getTransaction().begin();
+		testEntity1 = new TestEntity();
+		testEntity1.setId( 1L );
+		testEntity1.setString1( "abcdef" );
+		testEntity1.setString2( "42 - the truth" );
+		testEntity1.setInt1( 42 );
+		em.persist( testEntity1 );
+		em.getTransaction().commit();
+	}
+
+	@Test
+	public void testProjectionWithPropertyArgument() {
+		Object actual = getAuditReader().createQuery().forEntitiesAtRevision( TestEntity.class, 1 )
+				.addProjection( AuditEntity.function( "upper", AuditEntity.property( "string1" ) ) ).getSingleResult();
+		String expected = testEntity1.getString1().toUpperCase();
+		assertEquals( "Expected the property string1 to be upper case", expected, actual );
+	}
+
+	@Test
+	public void testProjectionWithPropertyAndSimpleArguments() {
+		Object actual = getAuditReader().createQuery().forEntitiesAtRevision( TestEntity.class, 1 )
+				.addProjection( AuditEntity.function( "substring", AuditEntity.property( "string1" ), 3, 2 ) ).getSingleResult();
+		// the sql substring indices are 1 based while java substring indices are 0 based
+		// the sql substring second parameter denotes the length of the substring
+		// while in java the scond argument denotes the end index
+		String expected = testEntity1.getString1().substring( 2, 4 );
+		assertEquals( "Expected the substring of the property string1", expected, actual );
+	}
+
+	@Test
+	public void testProjectionWithNestedFunction() {
+		Object actual = getAuditReader().createQuery().forEntitiesAtRevision( TestEntity.class, 1 )
+				.addProjection( AuditEntity.function( "concat",
+						AuditEntity.function( "upper", AuditEntity.property( "string1" ) ),
+						AuditEntity.function( "substring", AuditEntity.property( "string2" ), 1, 2 ) ) )
+				.getSingleResult();
+		final String expected = testEntity1.getString1().toUpperCase().concat( testEntity1.getString2().substring( 0, 2 ) );
+		assertEquals( "Expected the upper cased string1 to be concat with the first two characters of string2", expected, actual );
+	}
+
+	@Test
+	public void testComparisonFunctionWithValue() {
+		TestEntity entity = (TestEntity) getAuditReader().createQuery().forEntitiesAtRevision( TestEntity.class, 1 )
+				.add( AuditEntity.function( "substring", AuditEntity.property( "string1" ), 3, 2 ).eq( "cd" ) ).getSingleResult();
+		assertNotNull( "Expected the entity to be returned", entity );
+		assertEquals( "Expected the entity to be returned", testEntity1.getId(), entity.getId() );
+	}
+
+	@Test
+	public void testComparionFunctionWithProperty() {
+		TestEntity entity = (TestEntity) getAuditReader().createQuery().forEntitiesAtRevision( TestEntity.class, 1 )
+				.add( AuditEntity.function( "length", AuditEntity.property( "string2" ) ).ltProperty( "int1" ) ).getSingleResult();
+		assertNotNull( "Expected the entity to be returned", entity );
+		assertEquals( "Expected the entity to be returned", testEntity1.getId(), entity.getId() );
+	}
+
+	@Test
+	public void testComparisonFunctionWithFunction() {
+		TestEntity entity = (TestEntity) getAuditReader().createQuery().forEntitiesAtRevision( TestEntity.class, 1 )
+				.add( AuditEntity.function( "substring", AuditEntity.property( "string2" ), 1, 2 )
+						.eqFunction( AuditEntity.function( "str", AuditEntity.property( "int1" ) ) ) )
+				.getSingleResult();
+		assertNotNull( "Expected the entity to be returned", entity );
+		assertEquals( "Expected the entity to be returned", testEntity1.getId(), entity.getId() );
+	}
+
+	@Test
+	public void testComparisonPropertyWithFunction() {
+		TestEntity entity = (TestEntity) getAuditReader().createQuery().forEntitiesAtRevision( TestEntity.class, 1 )
+				.add( AuditEntity.property( "int1" ).gtFunction( AuditEntity.function( "length", AuditEntity.property( "string2" ) ) ) ).getSingleResult();
+		assertNotNull( "Expected the entity to be returned", entity );
+		assertEquals( "Expected the entity to be returned", testEntity1.getId(), entity.getId() );
+	}
+
+}