Adding a file missed in -- ZOOKEEPER-355. make validatePath non public in Zookeeper client api.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/zookeeper/trunk@763973 13f79535-47bb-0310-9956-ffa450edef68

src/java/main/org/apache/zookeeper/common/PathUtils.java

@@ -0,0 +1,103 @@
+ /**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.zookeeper.common;
+
+
+/**
+ * Path related utilities
+ */    
+public class PathUtils {
+	
+	/** validate the provided znode path string
+	 * @param path znode path string
+	 * @param isSequential if the path is being created
+	 * with a sequential flag
+	 * @throws IllegalArgumentException if the path is invalid
+	 */
+	public static void validatePath(String path, boolean isSequential) 
+		throws IllegalArgumentException {
+		validatePath(isSequential? path + "1": path);
+	}
+	
+    /**
+     * Validate the provided znode path string
+     * @param path znode path string
+     * @throws IllegalArgumentException if the path is invalid
+     */
+    public static void validatePath(String path) throws IllegalArgumentException {
+        if (path == null) {
+            throw new IllegalArgumentException("Path cannot be null");
+        }
+        if (path.length() == 0) {
+            throw new IllegalArgumentException("Path length must be > 0");
+        }
+        if (path.charAt(0) != '/') {
+            throw new IllegalArgumentException(
+                         "Path must start with / character");
+        }
+        if (path.length() == 1) { // done checking - it's the root
+            return;
+        }
+        if (path.charAt(path.length() - 1) == '/') {
+            throw new IllegalArgumentException(
+                         "Path must not end with / character");
+        }
+
+        String reason = null;
+        char lastc = '/';
+        char chars[] = path.toCharArray();
+        char c;
+        for (int i = 1; i < chars.length; lastc = chars[i], i++) {
+            c = chars[i];
+
+            if (c == 0) {
+                reason = "null character not allowed @" + i;
+                break;
+            } else if (c == '/' && lastc == '/') {
+                reason = "empty node name specified @" + i;
+                break;
+            } else if (c == '.' && lastc == '.') {
+                if (chars[i-2] == '/' &&
+                        ((i + 1 == chars.length)
+                                || chars[i+1] == '/')) {
+                    reason = "relative paths not allowed @" + i;
+                    break;
+                }
+            } else if (c == '.') {
+                if (chars[i-1] == '/' &&
+                        ((i + 1 == chars.length)
+                                || chars[i+1] == '/')) {
+                    reason = "relative paths not allowed @" + i;
+                    break;
+                }
+            } else if (c > '\u0000' && c < '\u001f'
+                    || c > '\u007f' && c < '\u009F'
+                    || c > '\ud800' && c < '\uf8ff'
+                    || c > '\ufff0' && c < '\uffff') {
+                reason = "invalid charater @" + i;
+                break;
+            }
+        }
+
+        if (reason != null) {
+            throw new IllegalArgumentException(
+                    "Invalid path string \"" + path + "\" caused by " + reason);
+        }
+    }
+}