HSEARCH-1161 Throw a more specific exception type on searching on mea…

…ningless input

hibernate-search-engine/src/main/java/org/hibernate/search/errors/EmptyQueryException.java

@@ -0,0 +1,53 @@
+/* 
+ * Hibernate, Relational Persistence for Idiomatic Java
+ * 
+ * JBoss, Home of Professional Open Source
+ * Copyright 2012 Red Hat Inc. and/or its affiliates and other contributors
+ * as indicated by the @authors tag. All rights reserved.
+ * See the copyright.txt in the distribution for a
+ * full listing of individual contributors.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License, v. 2.1.
+ * This program is distributed in the hope that it will be useful, but WITHOUT A
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
+ * You should have received a copy of the GNU Lesser General Public License,
+ * v.2.1 along with this distribution; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA  02110-1301, USA.
+ */
+package org.hibernate.search.errors;
+
+import org.hibernate.search.SearchException;
+
+
+/**
+ * This Exception is thrown when an empty TermQuery (keyword query) is created,
+ * or if any string query only returns whitespace after applying Analyzers.
+ * 
+ * Applications should validate user input before running such a Query;
+ * 
+ * @see org.hibernate.search.util.AnalyzerUtils
+ * @author Sanne Grinovero <sanne@hibernate.org> (C) 2012 Red Hat Inc.
+ */
+public class EmptyQueryException extends SearchException {
+
+	public EmptyQueryException() {
+		super();
+	}
+
+	public EmptyQueryException(String message) {
+		super( message );
+	}
+
+	public EmptyQueryException(String message, Throwable cause) {
+		super( message, cause );
+	}
+
+	public EmptyQueryException(Throwable cause) {
+		super( cause );
+	}
+
+}

hibernate-search-engine/src/main/java/org/hibernate/search/query/dsl/impl/ConnectedMultiFieldsTermQueryBuilder.java

@@ -46,11 +46,16 @@
 import org.hibernate.search.bridge.util.impl.NumericFieldUtils;
 import org.hibernate.search.engine.spi.DocumentBuilderIndexedEntity;
 import org.hibernate.search.query.dsl.TermTermination;
+import org.hibernate.search.util.logging.impl.Log;
+import org.hibernate.search.util.logging.impl.LoggerFactory;
 
 /**
  * @author Emmanuel Bernard
  */
 public class ConnectedMultiFieldsTermQueryBuilder implements TermTermination {
+
+	private static final Log log = LoggerFactory.make();
+
 	private final Object value;
 	private final QueryCustomizer queryCustomizer;
 	private final TermQueryContext termContext;
@@ -103,7 +108,7 @@ private Query createQuery(FieldContext fieldContext, ConversionContext conversio
 			);
 
 			if ( terms.size() == 0 ) {
-				throw new SearchException( "Try to search with an empty string: " + fieldContext.getField() );
+				throw log.queryWithNoTermsAfterAnalysis( fieldContext.getField(), searchTerm );
 			}
 			else if ( terms.size() == 1 ) {
 				perFieldQuery = createTermQuery( fieldContext, terms.get( 0 ) );

hibernate-search-engine/src/main/java/org/hibernate/search/util/logging/impl/Log.java

@@ -37,6 +37,7 @@
 import org.hibernate.search.SearchException;
 import org.hibernate.search.backend.impl.jgroups.JGroupsChannelProvider;
 import org.hibernate.search.backend.spi.WorkType;
+import org.hibernate.search.errors.EmptyQueryException;
 
 import static org.jboss.logging.Logger.Level.ERROR;
 import static org.jboss.logging.Logger.Level.INFO;
@@ -551,9 +552,14 @@ public interface Log extends BasicLogger {
 			"not as an IndexManager property for index '%1$s'. See http://docs.jboss.org/hibernate/search/4.1/reference/en-US/html_single/#jgroups-backend")
 	SearchException legacyJGroupsConfigurationDefined(String indexName);
 
+	@Message(id = 131, value = "The query string '%2$s' applied on field '%1$s' has no meaningfull tokens to be matched. Validate the query input " +
+			"against the Analyzer applied on this field.")
+	EmptyQueryException queryWithNoTermsAfterAnalysis(String field, String searchTerm);
+
 	@Message(id = 132, value = "Configured JGroups channel is a Muxer! MuxId option is required: define '" + JGroupsChannelProvider.MUX_ID + "'.")
 	SearchException missingJGroupsMuxId();
 
 	@Message(id = 133, value = "MuxId '%1$d' configured on the JGroups was already taken. Can't register handler!")
 	SearchException jGroupsMuxIdAlreadyTaken(short n);
+
 }

hibernate-search-engine/src/test/java/org/hibernate/search/test/dsl/EmptyQueryExceptionTest.java

@@ -0,0 +1,81 @@
+/* 
+ * Hibernate, Relational Persistence for Idiomatic Java
+ * 
+ * JBoss, Home of Professional Open Source
+ * Copyright 2012 Red Hat Inc. and/or its affiliates and other contributors
+ * as indicated by the @authors tag. All rights reserved.
+ * See the copyright.txt in the distribution for a
+ * full listing of individual contributors.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License, v. 2.1.
+ * This program is distributed in the hope that it will be useful, but WITHOUT A
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
+ * You should have received a copy of the GNU Lesser General Public License,
+ * v.2.1 along with this distribution; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA  02110-1301, USA.
+ */
+package org.hibernate.search.test.dsl;
+
+import org.hibernate.search.annotations.DocumentId;
+import org.hibernate.search.annotations.Field;
+import org.hibernate.search.annotations.Indexed;
+import org.hibernate.search.backend.spi.Work;
+import org.hibernate.search.backend.spi.WorkType;
+import org.hibernate.search.engine.spi.SearchFactoryImplementor;
+import org.hibernate.search.errors.EmptyQueryException;
+import org.hibernate.search.query.dsl.QueryBuilder;
+import org.hibernate.search.test.programmaticmapping.TestingSearchFactoryHolder;
+import org.hibernate.search.test.util.ManualTransactionContext;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+
+
+/**
+ * Verifies an EmptyQueryException is thrown when appropriate.
+ * 
+ * @author Sanne Grinovero <sanne@hibernate.org> (C) 2012 Red Hat Inc.
+ */
+public class EmptyQueryExceptionTest {
+
+	@Rule
+	public TestingSearchFactoryHolder sfHolder = new TestingSearchFactoryHolder( Book.class );
+
+	@Rule
+	public ExpectedException exceptions = ExpectedException.none();
+
+	@Test
+	public void verifyExceptionOnNonMeaningfullQueries() {
+		final SearchFactoryImplementor searchFactory = sfHolder.getSearchFactory();
+
+		Book book = new Book();
+		book.title = "Empty Book";
+		book.text = "The question is, does an empty book have 'space' tokens in it?";
+
+		Work work = new Work( book, book.title, WorkType.ADD, false );
+		ManualTransactionContext tc = new ManualTransactionContext();
+		searchFactory.getWorker().performWork( work, tc );
+		tc.end();
+
+		QueryBuilder queryBuilder = searchFactory.buildQueryBuilder().forEntity( Book.class ).get();
+
+		exceptions.expect( EmptyQueryException.class );
+
+		queryBuilder.keyword().onField( "text" ).matching( " " ).createQuery();
+		// Hence the answer is: a program won't be able to tell you.
+	}
+
+	@Indexed
+	static class Book {
+		@DocumentId
+		String title;
+
+		@Field
+		String text;
+	}
+
+}

hibernate-search-engine/src/test/java/org/hibernate/search/test/programmaticmapping/TestingSearchFactoryHolder.java

@@ -36,9 +36,15 @@ public class TestingSearchFactoryHolder extends ExternalResource {
 
 	private final SearchMapping buildMappingDefinition;
 	private SearchFactoryImplementor sf;
+	private final Class<?>[] entities;
 
-	public TestingSearchFactoryHolder(SearchMapping buildMappingDefinition) {
+	public TestingSearchFactoryHolder(Class<?>... entities) {
+		this( null, entities );
+	}
+
+	public TestingSearchFactoryHolder(SearchMapping buildMappingDefinition, Class<?>... entities) {
 		this.buildMappingDefinition = buildMappingDefinition;
+		this.entities = entities;
 	}
 
 	public SearchFactoryImplementor getSearchFactory() {
@@ -50,6 +56,9 @@ protected void before() throws Throwable {
 		ManualConfiguration cfg = new ManualConfiguration();
 		cfg.setProgrammaticMapping( buildMappingDefinition );
 		cfg.addProperty( "hibernate.search.default.directory_provider", "ram" );
+		for ( Class<?> c : entities ) {
+			cfg.addClass( c );
+		}
 		sf = new SearchFactoryBuilder().configuration( cfg ).buildSearchFactory();
 	}