Initial revision

From-SVN: r102074

libjava/classpath/java/util/regex/Pattern.java

@@ -0,0 +1,254 @@
+/* Pattern.java -- Compiled regular expression ready to be applied.
+   Copyright (C) 2002, 2004, 2005 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath 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 for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+package java.util.regex;
+
+import gnu.regexp.RE;
+import gnu.regexp.REException;
+import gnu.regexp.RESyntax;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+
+
+/**
+ * Compiled regular expression ready to be applied. 
+ *
+ * @since 1.4
+ */
+public final class Pattern implements Serializable
+{
+  private static final long serialVersionUID = 5073258162644648461L;
+  
+  public static final int CANON_EQ = 128;
+  public static final int CASE_INSENSITIVE = 2;
+  public static final int COMMENTS = 4;
+  public static final int DOTALL = 32;
+  public static final int MULTILINE = 8;
+  public static final int UNICODE_CASE = 64;
+  public static final int UNIX_LINES = 1;
+  
+  private final String regex;
+  private final int flags;
+
+  private final RE re;
+
+  private Pattern (String regex, int flags)
+    throws PatternSyntaxException
+  {
+    this.regex = regex;
+    this.flags = flags;
+
+    int gnuFlags = 0;
+    if ((flags & CASE_INSENSITIVE) != 0)
+      gnuFlags |= RE.REG_ICASE;
+    if ((flags & MULTILINE) != 0)
+      gnuFlags |= RE.REG_MULTILINE;
+    if ((flags & DOTALL) != 0)
+      gnuFlags |= RE.REG_DOT_NEWLINE;
+    // not yet supported:
+    // if ((flags & UNICODE_CASE) != 0) gnuFlags =
+    // if ((flags & CANON_EQ) != 0) gnuFlags =
+
+    RESyntax syntax = RESyntax.RE_SYNTAX_JAVA_1_4;
+    if ((flags & UNIX_LINES) != 0)
+      {
+	// Use a syntax set with \n for linefeeds?
+	syntax = new RESyntax(syntax);
+	syntax.setLineSeparator("\n");
+      }
+
+    if ((flags & COMMENTS) != 0)
+      {
+	// Use a syntax with support for comments?
+      }
+
+    try
+      {
+	this.re = new RE(regex, gnuFlags, syntax);
+      }
+    catch (REException e)
+      {
+	throw new PatternSyntaxException(e.getMessage(),
+					 regex, e.getPosition());
+      }
+  }
+ 
+  // package private accessor method
+  RE getRE()
+  {
+    return re;
+  }
+
+  /**
+   * @param regex The regular expression
+   *
+   * @exception PatternSyntaxException If the expression's syntax is invalid
+   */
+  public static Pattern compile (String regex)
+    throws PatternSyntaxException
+  {
+    return compile(regex, 0);
+  }
+  
+  /**
+   * @param regex The regular expression
+   * @param flags The match flags, a bit mask
+   *
+   * @exception PatternSyntaxException If the expression's syntax is invalid
+   * @exception IllegalArgumentException If bit values other than those
+   * corresponding to the defined match flags are set in flags
+   */
+  public static Pattern compile (String regex, int flags)
+    throws PatternSyntaxException
+  {
+    // FIXME: check which flags are really accepted
+    if ((flags & ~0xEF) != 0)
+      throw new IllegalArgumentException ();
+    
+    return new Pattern (regex, flags); 
+  }
+  
+  public int flags ()
+  {
+    return this.flags;
+  }
+  
+  /**
+   * @param regex The regular expression
+   * @param input The character sequence to be matched
+   *
+   * @exception PatternSyntaxException If the expression's syntax is invalid
+   */
+  public static boolean matches (String regex, CharSequence input) 
+  {
+    return compile(regex).matcher(input).matches();
+  }
+  
+  /**
+   * @param input The character sequence to be matched
+   */
+  public Matcher matcher (CharSequence input)
+  {
+    return new Matcher(this, input);
+  }
+  
+  /**
+   * @param input The character sequence to be matched
+   */
+  public String[] split (CharSequence input)
+  {
+    return split(input, 0);
+  }
+  
+  /**
+   * @param input The character sequence to be matched
+   * @param limit The result threshold
+   */
+  public String[] split (CharSequence input, int limit)
+  {
+    Matcher matcher = new Matcher(this, input);
+    ArrayList list = new ArrayList();
+    int empties = 0;
+    int count = 0;
+    int start = 0;
+    int end;
+    boolean matched = matcher.find();
+
+    while (matched && (limit <= 0 || count < limit - 1))
+      {
+	++count;
+	end = matcher.start();
+	if (start == end)
+	  empties++;
+	else
+	  {
+	    while (empties > 0)
+	      {
+		list.add("");
+		empties--;
+	      }
+
+	    String text = input.subSequence(start, end).toString();
+	    list.add(text);
+	  }
+	start = matcher.end();
+	matched = matcher.find();
+      }
+
+    // We matched nothing.
+    if (!matched && count == 0)
+      return new String[] { input.toString() };
+    
+    // Is the last token empty?
+    boolean emptyLast = (start == input.length());
+
+    // Can/Must we add empties or an extra last token at the end?
+    if (list.size() < limit || limit < 0 || (limit == 0 && !emptyLast))
+      {
+	if (limit > list.size())
+	  {
+	    int max = limit - list.size();
+	    empties = (empties > max) ? max : empties;
+	  }
+	while (empties > 0)
+	  {
+	    list.add("");
+	    empties--;
+	  }
+      }
+
+    // last token at end
+    if (limit != 0 || (limit == 0 && !emptyLast))
+      {
+	String t = input.subSequence(start, input.length()).toString();
+	if ("".equals(t) && limit == 0)
+	  ; // Don't add.
+	else
+	  list.add(t);
+      }
+
+    String[] output = new String [list.size()];
+    list.toArray(output);
+    return output;
+  }
+  
+  public String pattern ()
+  {
+    return regex;
+  }
+}