| /******************************************************************************* |
| * Copyright (c) 2003, 2016 IBM Corporation and others. |
| * |
| * This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License 2.0 |
| * which accompanies this distribution, and is available at |
| * https://www.eclipse.org/legal/epl-2.0/ |
| * |
| * SPDX-License-Identifier: EPL-2.0 |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| |
| package org.eclipse.osgi.internal.util; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| /** |
| * Simple tokenizer class. Used to parse data. |
| */ |
| public class Tokenizer { |
| protected char value[]; |
| protected int max; |
| protected int cursor; |
| |
| public Tokenizer(String value) { |
| this.value = value.toCharArray(); |
| max = this.value.length; |
| cursor = 0; |
| } |
| |
| private void skipWhiteSpace() { |
| char[] val = value; |
| int cur = cursor; |
| |
| for (; cur < max; cur++) { |
| char c = val[cur]; |
| if ((c == ' ') || (c == '\t') || (c == '\n') || (c == '\r')) { |
| continue; |
| } |
| break; |
| } |
| cursor = cur; |
| } |
| |
| public String getToken(String terminals) { |
| skipWhiteSpace(); |
| char[] val = value; |
| int cur = cursor; |
| |
| int begin = cur; |
| for (; cur < max; cur++) { |
| char c = val[cur]; |
| if ((terminals.indexOf(c) != -1)) { |
| break; |
| } |
| } |
| cursor = cur; |
| int count = cur - begin; |
| if (count > 0) { |
| skipWhiteSpace(); |
| while (count > 0 && (val[begin + count - 1] == ' ' || val[begin + count - 1] == '\t')) |
| count--; |
| return (new String(val, begin, count)); |
| } |
| return (null); |
| } |
| |
| public String getEscapedToken(String terminals) { |
| char[] val = value; |
| int cur = cursor; |
| if (cur >= max) |
| return null; |
| StringBuffer sb = new StringBuffer(); |
| char c; |
| for (; cur < max; cur++) { |
| c = val[cur]; |
| // this is an escaped char |
| if (c == '\\') { |
| cur++; // skip the escape char |
| if (cur == max) |
| break; |
| c = val[cur]; // include the escaped char |
| } else if (terminals.indexOf(c) != -1) { |
| break; |
| } |
| sb.append(c); |
| } |
| |
| cursor = cur; |
| return sb.toString(); |
| } |
| |
| public List<String> getEscapedTokens(String terminals) { |
| List<String> result = new ArrayList<>(); |
| for (String token = getEscapedToken(terminals); token != null; token = getEscapedToken(terminals)) { |
| result.add(token); |
| getChar(); // consume terminal |
| } |
| return result; |
| } |
| |
| public String getString(String terminals, String preserveEscapes) { |
| skipWhiteSpace(); |
| char[] val = value; |
| int cur = cursor; |
| |
| if (cur < max) { |
| if (val[cur] == '\"') /* if a quoted string */ |
| { |
| StringBuffer sb = new StringBuffer(); |
| cur++; /* skip quote */ |
| char c = '\0'; |
| for (; cur < max; cur++) { |
| c = val[cur]; |
| // this is an escaped char |
| if (c == '\\') { |
| cur++; // skip the escape char |
| if (cur == max) |
| break; |
| c = val[cur]; // include the escaped char |
| if (preserveEscapes != null && preserveEscapes.indexOf(c) != -1) |
| sb.append('\\'); // must preserve escapes for c |
| } else if (c == '\"') { |
| break; |
| } |
| sb.append(c); |
| } |
| |
| if (c == '\"') { |
| cur++; |
| } // TODO else error; no closing quote? |
| |
| cursor = cur; |
| skipWhiteSpace(); |
| return sb.toString(); |
| |
| } |
| /* not a quoted string; same as token */ |
| return getToken(terminals); |
| } |
| return (null); |
| } |
| |
| public String getString(String terminals) { |
| return getString(terminals, null); |
| } |
| |
| public char getChar() { |
| int cur = cursor; |
| if (cur < max) { |
| cursor = cur + 1; |
| return (value[cur]); |
| } |
| return ('\0'); /* end of value */ |
| } |
| |
| public boolean hasMoreTokens() { |
| if (cursor < max) { |
| return true; |
| } |
| return false; |
| } |
| } |