src/java.base/share/classes/java/util/regex/PrintPattern.java - platform/libcore - Git at Google

 /*
  * Copyright (c) 2016, Oracle and/or its affiliates. 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.  Oracle designates this
  * particular file as subject to the "Classpath" exception as provided
  * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */

 package java.util.regex;

 import java.util.HashMap;
 import java.util.regex.Pattern.CharPredicate;
 import static java.util.regex.ASCII.*;

 /**
  * A utility class to print out the pattern node tree.
  */

 class PrintPattern {

     private static HashMap<Pattern.Node, Integer> ids = new HashMap<>();

     private static void print(Pattern.Node node, String text, int depth) {
         if (!ids.containsKey(node))
             ids.put(node, ids.size());
         print("%6d:%" + (depth==0? "": depth<<1) + "s<%s>", ids.get(node), "", text);
         if (ids.containsKey(node.next))
             print(" (=>%d)", ids.get(node.next));
         print("%n");
     }

     private static void print(String s, int depth) {
         print("       %" + (depth==0?"":depth<<1) + "s<%s>%n", "", s);
     }

     private static void print(String fmt, Object ... args) {
         System.err.printf(fmt, args);
     }

     private static String toStringCPS(int[] cps) {
         StringBuilder sb = new StringBuilder(cps.length);
         for (int cp : cps)
             sb.append(toStringCP(cp));
         return sb.toString();
     }

     private static String toStringCP(int cp) {
         return (isPrint(cp) ? "" + (char)cp
                             : "\\u" + Integer.toString(cp, 16));
     }

     private static String toStringRange(int min, int max) {
        if (max == Pattern.MAX_REPS) {
            if (min == 0)
                return " * ";
            else if (min == 1)
                return " + ";
            return "{" + min + ", max}";
        }
        return "{" + min + ", " +  max + "}";
     }

     private static String toStringCtype(int type) {
         switch(type) {
         case UPPER:  return "ASCII.UPPER";
         case LOWER:  return "ASCII.LOWER";
         case DIGIT:  return "ASCII.DIGIT";
         case SPACE:  return "ASCII.SPACE";
         case PUNCT:  return "ASCII.PUNCT";
         case CNTRL:  return "ASCII.CNTRL";
         case BLANK:  return "ASCII.BLANK";
         case UNDER:  return "ASCII.UNDER";
         case ASCII:  return "ASCII.ASCII";
         case ALPHA:  return "ASCII.ALPHA";
         case ALNUM:  return "ASCII.ALNUM";
         case GRAPH:  return "ASCII.GRAPH";
         case WORD:   return "ASCII.WORD";
         case XDIGIT: return "ASCII.XDIGIT";
         default: return "ASCII ?";
         }
     }

     private static String toString(Pattern.Node node) {
         String name = node.getClass().getName();
         return name.substring(name.lastIndexOf('$') + 1);
     }

     static HashMap<CharPredicate, String> pmap;
     static {
         pmap = new HashMap<>();
         pmap.put(Pattern.ALL(), "All");
         pmap.put(Pattern.DOT(), "Dot");
         pmap.put(Pattern.UNIXDOT(), "UnixDot");
         pmap.put(Pattern.VertWS(), "VertWS");
         pmap.put(Pattern.HorizWS(), "HorizWS");

         pmap.put(CharPredicates.ASCII_DIGIT(), "ASCII.DIGIT");
         pmap.put(CharPredicates.ASCII_WORD(),  "ASCII.WORD");
         pmap.put(CharPredicates.ASCII_SPACE(), "ASCII.SPACE");
     }

     static void walk(Pattern.Node node, int depth) {
         depth++;
         while(node != null) {
             String name = toString(node);
             String str;
             if (node instanceof Pattern.Prolog) {
                 print(node, name, depth);
                 // print the loop here
                 Pattern.Loop loop = ((Pattern.Prolog)node).loop;
                 name = toString(loop);
                 str = name + " " + toStringRange(loop.cmin, loop.cmax);
                 print(loop, str, depth);
                 walk(loop.body, depth);
                 print("/" + name, depth);
                 node = loop;
             } else if (node instanceof Pattern.Loop) {
                 return;  // stop here, body.next -> loop
             } else if (node instanceof Pattern.Curly) {
                 Pattern.Curly c = (Pattern.Curly)node;
                 str = "Curly " + c.type + " " + toStringRange(c.cmin, c.cmax);
                 print(node, str, depth);
                 walk(c.atom, depth);
                 print("/Curly", depth);
             } else if (node instanceof Pattern.GroupCurly) {
                 Pattern.GroupCurly gc = (Pattern.GroupCurly)node;
                 str = "GroupCurly " + gc.groupIndex / 2 +
                       ", " + gc.type + " " + toStringRange(gc.cmin, gc.cmax);
                 print(node, str, depth);
                 walk(gc.atom, depth);
                 print("/GroupCurly", depth);
             } else if (node instanceof Pattern.GroupHead) {
                 Pattern.GroupHead head = (Pattern.GroupHead)node;
                 Pattern.GroupTail tail = head.tail;
                 print(head, "Group.head " + (tail.groupIndex / 2), depth);
                 walk(head.next, depth);
                 print(tail, "/Group.tail " + (tail.groupIndex / 2), depth);
                 node = tail;
             } else if (node instanceof Pattern.GroupTail) {
                 return;  // stopper
             } else if (node instanceof Pattern.Ques) {
                 print(node, "Ques " + ((Pattern.Ques)node).type, depth);
                 walk(((Pattern.Ques)node).atom, depth);
                 print("/Ques", depth);
             } else if (node instanceof Pattern.Branch) {
                 Pattern.Branch b = (Pattern.Branch)node;
                 print(b, name, depth);
                 int i = 0;
                 while (true) {
                     if (b.atoms[i] != null) {
                         walk(b.atoms[i], depth);
                     } else {
                         print("  (accepted)", depth);
                     }
                     if (++i == b.size)
                         break;
                     print("-branch.separator-", depth);
                 }
                 node = b.conn;
                 print(node, "/Branch", depth);
             } else if (node instanceof Pattern.BranchConn) {
                 return;
             } else if (node instanceof Pattern.CharProperty) {
                 str = pmap.get(((Pattern.CharProperty)node).predicate);
                 if (str == null)
                     str = toString(node);
                 else
                     str = "Single \"" + str + "\"";
                 print(node, str, depth);
             } else if (node instanceof Pattern.SliceNode) {
                 str = name + "  \"" +
                       toStringCPS(((Pattern.SliceNode)node).buffer) + "\"";
                 print(node, str, depth);
             } else if (node instanceof Pattern.CharPropertyGreedy) {
                 Pattern.CharPropertyGreedy gcp = (Pattern.CharPropertyGreedy)node;
                 String pstr = pmap.get(gcp.predicate);
                 if (pstr == null)
                     pstr = gcp.predicate.toString();
                 else
                     pstr = "Single \"" + pstr + "\"";
                 str = name + " " + pstr + ((gcp.cmin == 0) ? "*" : "+");
                 print(node, str, depth);
             } else if (node instanceof Pattern.BackRef) {
                 str = "GroupBackRef " + ((Pattern.BackRef)node).groupIndex / 2;
                 print(node, str, depth);
             } else if (node instanceof Pattern.LastNode) {
                 print(node, "END", depth);
             } else if (node == Pattern.accept) {
                 return;
             } else {
                 print(node, name, depth);
             }
             node = node.next;
         }
     }

     public static void main(String[] args) {
         Pattern p = Pattern.compile(args[0]);
         System.out.println("   Pattern: " + p);
         walk(p.root, 0);
     }
 }
	/*
	* Copyright (c) 2016, Oracle and/or its affiliates. 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. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.util.regex;

	import java.util.HashMap;
	import java.util.regex.Pattern.CharPredicate;
	import static java.util.regex.ASCII.*;

	/**
	* A utility class to print out the pattern node tree.
	*/

	class PrintPattern {

	private static HashMap<Pattern.Node, Integer> ids = new HashMap<>();

	private static void print(Pattern.Node node, String text, int depth) {
	if (!ids.containsKey(node))
	ids.put(node, ids.size());
	print("%6d:%" + (depth==0? "": depth<<1) + "s<%s>", ids.get(node), "", text);
	if (ids.containsKey(node.next))
	print(" (=>%d)", ids.get(node.next));
	print("%n");
	}

	private static void print(String s, int depth) {
	print(" %" + (depth==0?"":depth<<1) + "s<%s>%n", "", s);
	}

	private static void print(String fmt, Object ... args) {
	System.err.printf(fmt, args);
	}

	private static String toStringCPS(int[] cps) {
	StringBuilder sb = new StringBuilder(cps.length);
	for (int cp : cps)
	sb.append(toStringCP(cp));
	return sb.toString();
	}

	private static String toStringCP(int cp) {
	return (isPrint(cp) ? "" + (char)cp
	: "\\u" + Integer.toString(cp, 16));
	}

	private static String toStringRange(int min, int max) {
	if (max == Pattern.MAX_REPS) {
	if (min == 0)
	return " * ";
	else if (min == 1)
	return " + ";
	return "{" + min + ", max}";
	}
	return "{" + min + ", " + max + "}";
	}

	private static String toStringCtype(int type) {
	switch(type) {
	case UPPER: return "ASCII.UPPER";
	case LOWER: return "ASCII.LOWER";
	case DIGIT: return "ASCII.DIGIT";
	case SPACE: return "ASCII.SPACE";
	case PUNCT: return "ASCII.PUNCT";
	case CNTRL: return "ASCII.CNTRL";
	case BLANK: return "ASCII.BLANK";
	case UNDER: return "ASCII.UNDER";
	case ASCII: return "ASCII.ASCII";
	case ALPHA: return "ASCII.ALPHA";
	case ALNUM: return "ASCII.ALNUM";
	case GRAPH: return "ASCII.GRAPH";
	case WORD: return "ASCII.WORD";
	case XDIGIT: return "ASCII.XDIGIT";
	default: return "ASCII ?";
	}
	}

	private static String toString(Pattern.Node node) {
	String name = node.getClass().getName();
	return name.substring(name.lastIndexOf('$') + 1);
	}

	static HashMap<CharPredicate, String> pmap;
	static {
	pmap = new HashMap<>();
	pmap.put(Pattern.ALL(), "All");
	pmap.put(Pattern.DOT(), "Dot");
	pmap.put(Pattern.UNIXDOT(), "UnixDot");
	pmap.put(Pattern.VertWS(), "VertWS");
	pmap.put(Pattern.HorizWS(), "HorizWS");

	pmap.put(CharPredicates.ASCII_DIGIT(), "ASCII.DIGIT");
	pmap.put(CharPredicates.ASCII_WORD(), "ASCII.WORD");
	pmap.put(CharPredicates.ASCII_SPACE(), "ASCII.SPACE");
	}

	static void walk(Pattern.Node node, int depth) {
	depth++;
	while(node != null) {
	String name = toString(node);
	String str;
	if (node instanceof Pattern.Prolog) {
	print(node, name, depth);
	// print the loop here
	Pattern.Loop loop = ((Pattern.Prolog)node).loop;
	name = toString(loop);
	str = name + " " + toStringRange(loop.cmin, loop.cmax);
	print(loop, str, depth);
	walk(loop.body, depth);
	print("/" + name, depth);
	node = loop;
	} else if (node instanceof Pattern.Loop) {
	return; // stop here, body.next -> loop
	} else if (node instanceof Pattern.Curly) {
	Pattern.Curly c = (Pattern.Curly)node;
	str = "Curly " + c.type + " " + toStringRange(c.cmin, c.cmax);
	print(node, str, depth);
	walk(c.atom, depth);
	print("/Curly", depth);
	} else if (node instanceof Pattern.GroupCurly) {
	Pattern.GroupCurly gc = (Pattern.GroupCurly)node;
	str = "GroupCurly " + gc.groupIndex / 2 +
	", " + gc.type + " " + toStringRange(gc.cmin, gc.cmax);
	print(node, str, depth);
	walk(gc.atom, depth);
	print("/GroupCurly", depth);
	} else if (node instanceof Pattern.GroupHead) {
	Pattern.GroupHead head = (Pattern.GroupHead)node;
	Pattern.GroupTail tail = head.tail;
	print(head, "Group.head " + (tail.groupIndex / 2), depth);
	walk(head.next, depth);
	print(tail, "/Group.tail " + (tail.groupIndex / 2), depth);
	node = tail;
	} else if (node instanceof Pattern.GroupTail) {
	return; // stopper
	} else if (node instanceof Pattern.Ques) {
	print(node, "Ques " + ((Pattern.Ques)node).type, depth);
	walk(((Pattern.Ques)node).atom, depth);
	print("/Ques", depth);
	} else if (node instanceof Pattern.Branch) {
	Pattern.Branch b = (Pattern.Branch)node;
	print(b, name, depth);
	int i = 0;
	while (true) {
	if (b.atoms[i] != null) {
	walk(b.atoms[i], depth);
	} else {
	print(" (accepted)", depth);
	}
	if (++i == b.size)
	break;
	print("-branch.separator-", depth);
	}
	node = b.conn;
	print(node, "/Branch", depth);
	} else if (node instanceof Pattern.BranchConn) {
	return;
	} else if (node instanceof Pattern.CharProperty) {
	str = pmap.get(((Pattern.CharProperty)node).predicate);
	if (str == null)
	str = toString(node);
	else
	str = "Single \"" + str + "\"";
	print(node, str, depth);
	} else if (node instanceof Pattern.SliceNode) {
	str = name + " \"" +
	toStringCPS(((Pattern.SliceNode)node).buffer) + "\"";
	print(node, str, depth);
	} else if (node instanceof Pattern.CharPropertyGreedy) {
	Pattern.CharPropertyGreedy gcp = (Pattern.CharPropertyGreedy)node;
	String pstr = pmap.get(gcp.predicate);
	if (pstr == null)
	pstr = gcp.predicate.toString();
	else
	pstr = "Single \"" + pstr + "\"";
	str = name + " " + pstr + ((gcp.cmin == 0) ? "*" : "+");
	print(node, str, depth);
	} else if (node instanceof Pattern.BackRef) {
	str = "GroupBackRef " + ((Pattern.BackRef)node).groupIndex / 2;
	print(node, str, depth);
	} else if (node instanceof Pattern.LastNode) {
	print(node, "END", depth);
	} else if (node == Pattern.accept) {
	return;
	} else {
	print(node, name, depth);
	}
	node = node.next;
	}
	}

	public static void main(String[] args) {
	Pattern p = Pattern.compile(args[0]);
	System.out.println(" Pattern: " + p);
	walk(p.root, 0);
	}
	}