jdk/src/share/classes/sun/nio/fs/Globs.java
changeset 2057 3acf8e5e2ca0
child 5506 202f599c92aa
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/sun/nio/fs/Globs.java	Sun Feb 15 12:25:54 2009 +0000
@@ -0,0 +1,217 @@
+/*
+ * Copyright 2008-2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package sun.nio.fs;
+
+import java.util.regex.PatternSyntaxException;
+
+public class Globs {
+    private Globs() { }
+
+    private static final String regexMetaChars = ".^$+{[]|()";
+    private static final String globMetaChars = "\\*?[{";
+
+    private static boolean isRegexMeta(char c) {
+        return regexMetaChars.indexOf(c) != -1;
+    }
+
+    private static boolean isGlobMeta(char c) {
+        return globMetaChars.indexOf(c) != -1;
+    }
+    private static char EOL = 0;  //TBD
+
+    private static char next(String glob, int i) {
+        if (i < glob.length()) {
+            return glob.charAt(i);
+        }
+        return EOL;
+    }
+
+    /**
+     * Creates a regex pattern from the given glob expression.
+     *
+     * @throws  PatternSyntaxException
+     */
+    private static String toRegexPattern(String globPattern, boolean isDos) {
+        boolean inGroup = false;
+        StringBuilder regex = new StringBuilder("^");
+
+        int i = 0;
+        while (i < globPattern.length()) {
+            char c = globPattern.charAt(i++);
+            switch (c) {
+                case '\\':
+                    // escape special characters
+                    if (i == globPattern.length()) {
+                        throw new PatternSyntaxException("No character to escape",
+                                globPattern, i - 1);
+                    }
+                    char next = globPattern.charAt(i++);
+                    if (isGlobMeta(next) || isRegexMeta(next)) {
+                        regex.append('\\');
+                    }
+                    regex.append(next);
+                    break;
+                case '/':
+                    if (isDos) {
+                        regex.append("\\\\");
+                    } else {
+                        regex.append(c);
+                    }
+                    break;
+                case '[':
+                    // don't match name separator in class
+                    if (isDos) {
+                        regex.append("[[^\\\\]&&[");
+                    } else {
+                        regex.append("[[^/]&&[");
+                    }
+                    if (next(globPattern, i) == '^') {
+                        // escape the regex negation char if it appears
+                        regex.append("\\^");
+                        i++;
+                    } else {
+                        // negation
+                        if (next(globPattern, i) == '!') {
+                            regex.append('^');
+                            i++;
+                        }
+                        // hyphen allowed at start
+                        if (next(globPattern, i) == '-') {
+                            regex.append('-');
+                            i++;
+                        }
+                    }
+                    boolean hasRangeStart = false;
+                    char last = 0;
+                    while (i < globPattern.length()) {
+                        c = globPattern.charAt(i++);
+                        if (c == ']') {
+                            break;
+                        }
+                        if (c == '/' || (isDos && c == '\\')) {
+                            throw new PatternSyntaxException("Explicit 'name separator' in class",
+                                    globPattern, i - 1);
+                        }
+                        // TBD: how to specify ']' in a class?
+                        if (c == '\\' || c == '[' ||
+                                c == '&' && next(globPattern, i) == '&') {
+                            // escape '\', '[' or "&&" for regex class
+                            regex.append('\\');
+                        }
+                        regex.append(c);
+
+                        if (c == '-') {
+                            if (!hasRangeStart) {
+                                throw new PatternSyntaxException("Invalid range",
+                                        globPattern, i - 1);
+                            }
+                            if ((c = next(globPattern, i++)) == EOL || c == ']') {
+                                break;
+                            }
+                            if (c < last) {
+                                throw new PatternSyntaxException("Invalid range",
+                                        globPattern, i - 3);
+                            }
+                            regex.append(c);
+                            hasRangeStart = false;
+                        } else {
+                            hasRangeStart = true;
+                            last = c;
+                        }
+                    }
+                    if (c != ']') {
+                        throw new PatternSyntaxException("Missing ']", globPattern, i - 1);
+                    }
+                    regex.append("]]");
+                    break;
+                case '{':
+                    if (inGroup) {
+                        throw new PatternSyntaxException("Cannot nest groups",
+                                globPattern, i - 1);
+                    }
+                    regex.append("(?:(?:");
+                    inGroup = true;
+                    break;
+                case '}':
+                    if (inGroup) {
+                        regex.append("))");
+                        inGroup = false;
+                    } else {
+                        regex.append('}');
+                    }
+                    break;
+                case ',':
+                    if (inGroup) {
+                        regex.append(")|(?:");
+                    } else {
+                        regex.append(',');
+                    }
+                    break;
+                case '*':
+                    if (next(globPattern, i) == '*') {
+                        // crosses directory boundaries
+                        regex.append(".*");
+                        i++;
+                    } else {
+                        // within directory boundary
+                        if (isDos) {
+                            regex.append("[^\\\\]*");
+                        } else {
+                            regex.append("[^/]*");
+                        }
+                    }
+                    break;
+                case '?':
+                   if (isDos) {
+                       regex.append("[^\\\\]");
+                   } else {
+                       regex.append("[^/]");
+                   }
+                   break;
+
+                default:
+                    if (isRegexMeta(c)) {
+                        regex.append('\\');
+                    }
+                    regex.append(c);
+            }
+        }
+
+        if (inGroup) {
+            throw new PatternSyntaxException("Missing '}", globPattern, i - 1);
+        }
+
+        return regex.append('$').toString();
+    }
+
+    static String toUnixRegexPattern(String globPattern) {
+        return toRegexPattern(globPattern, false);
+    }
+
+    static String toWindowsRegexPattern(String globPattern) {
+        return toRegexPattern(globPattern, true);
+    }
+}