Make the IMatcher public API

Provide a static factory method to create a PathMatcher.

Bug: 559526
Change-Id: Ib7a4a1bcc658ac2f2a09d365b5b891669dfd7570
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesRule.java

  */
 package org.eclipse.jgit.attributes;
 
-import static org.eclipse.jgit.ignore.internal.IMatcher.NO_MATCH;
+import static org.eclipse.jgit.ignore.IMatcher.NO_MATCH;
 
 import java.util.ArrayList;
 import java.util.Collections;
 import org.eclipse.jgit.attributes.Attribute.State;
 import org.eclipse.jgit.errors.InvalidPatternException;
 import org.eclipse.jgit.ignore.FastIgnoreRule;
-import org.eclipse.jgit.ignore.internal.IMatcher;
+import org.eclipse.jgit.ignore.IMatcher;
 import org.eclipse.jgit.ignore.internal.PathMatcher;
 
 /**

org.eclipse.jgit/src/org/eclipse/jgit/ignore/FastIgnoreRule.java

  */
 package org.eclipse.jgit.ignore;
 
-import static org.eclipse.jgit.ignore.internal.IMatcher.NO_MATCH;
+import static org.eclipse.jgit.ignore.IMatcher.NO_MATCH;
 import static org.eclipse.jgit.ignore.internal.Strings.isDirectoryPattern;
 import static org.eclipse.jgit.ignore.internal.Strings.stripTrailing;
 import static org.eclipse.jgit.ignore.internal.Strings.stripTrailingWhitespace;
 
 import org.eclipse.jgit.errors.InvalidPatternException;
-import org.eclipse.jgit.ignore.internal.IMatcher;
 import org.eclipse.jgit.ignore.internal.PathMatcher;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

org.eclipse.jgit/src/org/eclipse/jgit/ignore/internal/IMatcher.java → org.eclipse.jgit/src/org/eclipse/jgit/ignore/IMatcher.java

 /*
- * Copyright (C) 2014, 2017 Andrey Loskutov <loskutov@gmx.de> and others
+ * Copyright (C) 2014, 2020 Andrey Loskutov <loskutov@gmx.de> and others
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Distribution License v. 1.0 which is available at
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
-package org.eclipse.jgit.ignore.internal;
+package org.eclipse.jgit.ignore;
+
+import org.eclipse.jgit.annotations.NonNull;
+import org.eclipse.jgit.errors.InvalidPatternException;
+import org.eclipse.jgit.ignore.internal.PathMatcher;
 
 /**
- * Generic string matcher
+ * Generic path matcher.
+ *
+ * @since 5.7
  */
 public interface IMatcher {
 
 	 * Matcher that does not match any pattern.
 	 */
 	public static final IMatcher NO_MATCH = new IMatcher() {
+
 		@Override
 		public boolean matches(String path, boolean assumeDirectory,
 				boolean pathMatch) {
 		}
 	};
 
+	/**
+	 * Creates a path matcher for the given pattern. A pattern may contain the
+	 * wildcards "?", "*", and "**". The directory separator is '/'.
+	 *
+	 * @param pattern
+	 *            to match
+	 * @param dirOnly
+	 *            whether to match only directories
+	 * @return a matcher for the given pattern
+	 * @throws InvalidPatternException
+	 *             if the pattern is invalid
+	 */
+	@NonNull
+	public static IMatcher createPathMatcher(@NonNull String pattern,
+			boolean dirOnly) throws InvalidPatternException {
+		return PathMatcher.createPathMatcher(pattern,
+				Character.valueOf(FastIgnoreRule.PATH_SEPARATOR), dirOnly);
+	}
+
 	/**
 	 * Matches entire given string
 	 *
 	 *            with a slash)
 	 * @param pathMatch
 	 *            {@code true} if the match is for the full path: prefix-only
-	 *            matches are not allowed, and
-	 *            {@link org.eclipse.jgit.ignore.internal.NameMatcher}s must
-	 *            match only the last component (if they can -- they may not, if
-	 *            they are anchored at the beginning)
+	 *            matches are not allowed
 	 * @return true if this matcher pattern matches given string
 	 */
 	boolean matches(String path, boolean assumeDirectory, boolean pathMatch);

org.eclipse.jgit/src/org/eclipse/jgit/ignore/internal/AbstractMatcher.java

  */
 package org.eclipse.jgit.ignore.internal;
 
+import org.eclipse.jgit.ignore.IMatcher;
+
 /**
  * Base class for default methods as {@link #toString()} and such.
  * <p>

org.eclipse.jgit/src/org/eclipse/jgit/ignore/internal/PathMatcher.java

 import java.util.List;
 
 import org.eclipse.jgit.errors.InvalidPatternException;
+import org.eclipse.jgit.ignore.IMatcher;
 import org.eclipse.jgit.ignore.internal.Strings.PatternState;
 
 /**