DATACMNS-448 - Added infrastructure for 'deleteBy' queries.

Add keywords 'delete' and 'remove' to PartTree indicating presence of delete intend.

Original pull request: #72.

src/main/java/org/springframework/data/repository/query/parser/PartTree.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2008-2013 the original author or authors.
+ * Copyright 2008-2014 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -35,10 +35,14 @@ import org.springframework.util.StringUtils;
  * 
  * @author Oliver Gierke
  * @author Thomas Darimont
+ * @author Christoph Strobl
  */
 public class PartTree implements Iterable<OrPart> {
 
-	private static final Pattern PREFIX_TEMPLATE = Pattern.compile("^(find|read|get|count|query)(\\p{Lu}.*?)??By");
+	private static final String DELETE_PATTERN = "delete|remove";
+
+	private static final Pattern PREFIX_TEMPLATE = Pattern.compile("^(find|read|get|count|query|" + DELETE_PATTERN
+			+ ")(\\p{Lu}.*?)??By");
 
 	/*
 	 * We look for a pattern of: keyword followed by
@@ -121,6 +125,16 @@ public class PartTree implements Iterable<OrPart> {
 		return subject.isCountProjection();
 	}
 
+	/**
+	 * return true if the created {@link PartTree} is meant to be used for delete operation.
+	 * 
+	 * @return
+	 * @since 1.8
+	 */
+	public Boolean isDelete() {
+		return subject.isDelete();
+	}
+
 	/**
 	 * Returns an {@link Iterable} of all parts contained in the {@link PartTree}.
 	 * 
@@ -221,19 +235,33 @@ public class PartTree implements Iterable<OrPart> {
 	 * 
 	 * @author Phil Webb
 	 * @author Oliver Gierke
+	 * @author Christoph Strobl
 	 */
 	private static class Subject {
 
 		private static final String DISTINCT = "Distinct";
 		private static final Pattern COUNT_BY_TEMPLATE = Pattern.compile("^count(\\p{Lu}.*?)??By");
+		private static final Pattern DELETE_BY_TEMPLATE = Pattern.compile("^(" + DELETE_PATTERN + ")(\\p{Lu}.*?)??By");
 
 		private final boolean distinct;
 		private final boolean count;
+		private final boolean delete;
 
 		public Subject(String subject) {
 
 			this.distinct = subject == null ? false : subject.contains(DISTINCT);
-			this.count = subject == null ? false : COUNT_BY_TEMPLATE.matcher(subject).find();
+			this.count = matches(subject, COUNT_BY_TEMPLATE);
+			this.delete = matches(subject, DELETE_BY_TEMPLATE);
+		}
+
+		/**
+		 * Returns {@literal true} if {@link Subject} matches {@link #DELETE_BY_TEMPLATE}.
+		 * 
+		 * @return
+		 * @since 1.8
+		 */
+		public Boolean isDelete() {
+			return delete;
 		}
 
 		public boolean isCountProjection() {
@@ -243,6 +271,10 @@ public class PartTree implements Iterable<OrPart> {
 		public boolean isDistinct() {
 			return distinct;
 		}
+
+		private final boolean matches(String subject, Pattern pattern) {
+			return subject == null ? false : pattern.matcher(subject).find();
+		}
 	}
 
 	/**

src/test/java/org/springframework/data/repository/query/parser/PartTreeUnitTests.java

@@ -42,10 +42,11 @@ import org.springframework.data.repository.query.parser.PartTree.OrPart;
  * @author Phillip Webb
  * @author Thomas Darimont
  * @author Martin Baumgartner
+ * @author Christoph Strobl
  */
 public class PartTreeUnitTests {
 
-	private String[] PREFIXES = { "find", "read", "get", "query" };
+	private String[] PREFIXES = { "find", "read", "get", "query", "count", "delete", "remove" };
 
 	@Test(expected = IllegalArgumentException.class)
 	public void rejectsNullSource() throws Exception {
@@ -296,7 +297,7 @@ public class PartTreeUnitTests {
 	public void parsesBeforeKeywordCorrectly() {
 		assertType(Arrays.asList("birthdayBefore", "birthdayIsBefore"), Type.BEFORE, "birthday");
 	}
-	
+
 	/**
 	 * @see DATACMNS-433
 	 */
@@ -304,7 +305,7 @@ public class PartTreeUnitTests {
 	public void parsesLikeKeywordCorrectly() {
 		assertType(asList("activeLike", "activeIsLike"), LIKE, "active");
 	}
-	
+
 	/**
 	 * @see DATACMNS-433
 	 */
@@ -512,6 +513,46 @@ public class PartTreeUnitTests {
 		assertThat(tree.getSort(), is(new Sort(Direction.ASC, "lastname")));
 	}
 
+	/**
+	 * @see DATACMNS-448
+	 */
+	@Test
+	public void identifiesSimpleDeleteByCorrectly() {
+
+		PartTree tree = new PartTree("deleteByLastname", User.class);
+		assertThat(tree.isDelete(), is(true));
+	}
+
+	/**
+	 * @see DATACMNS-448
+	 */
+	@Test
+	public void identifiesExtendedDeleteByCorrectly() {
+
+		PartTree tree = new PartTree("deleteUserByLastname", User.class);
+		assertThat(tree.isDelete(), is(true));
+	}
+
+	/**
+	 * @see DATACMNS-448
+	 */
+	@Test
+	public void identifiesSimpleRemoveByCorrectly() {
+
+		PartTree tree = new PartTree("removeByLastname", User.class);
+		assertThat(tree.isDelete(), is(true));
+	}
+
+	/**
+	 * @see DATACMNS-448
+	 */
+	@Test
+	public void identifiesExtendedRemoveByCorrectly() {
+
+		PartTree tree = new PartTree("removeUserByLastname", User.class);
+		assertThat(tree.isDelete(), is(true));
+	}
+
 	private static void assertType(Iterable<String> sources, Type type, String property) {
 		assertType(sources, type, property, 1, true);
 	}