Source code

001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   https://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019
020package org.apache.commons.exec.util;
021
022import java.io.File;
023import java.util.ArrayList;
024import java.util.List;
025import java.util.Map;
026import java.util.Objects;
027import java.util.StringTokenizer;
028
029/**
030 * Supplement of commons-lang, the stringSubstitution() was in a simpler implementation available in an older commons-lang implementation.
031 *
032 * This class is not part of the public API and could change without warning.
033 */
034public class StringUtils {
035
036    /** Empty array. */
037    private static final String[] EMPTY_STRING_ARRAY = {};
038
039    /** Single quote. */
040    private static final String SINGLE_QUOTE = "\'";
041
042    /** Double quote. */
043    private static final String DOUBLE_QUOTE = "\"";
044
045    /** Forward lash character. */
046    private static final char SLASH_CHAR = '/';
047
048    /** Backlash character. */
049    private static final char BACKSLASH_CHAR = '\\';
050
051    /**
052     * Fixes the file separator char for the target platform using the following replacement.
053     * <ul>
054     * <li>'/' &#x2192; File.separatorChar</li>
055     * <li>'\\' &#x2192; File.separatorChar</li>
056     * </ul>
057     *
058     * @param arg the argument to fix.
059     * @return the transformed argument.
060     */
061    public static String fixFileSeparatorChar(final String arg) {
062        return arg.replace(SLASH_CHAR, File.separatorChar).replace(BACKSLASH_CHAR, File.separatorChar);
063    }
064
065    /**
066     * Determines if this is a quoted argument - either single or double-quoted.
067     *
068     * @param argument the argument to check.
069     * @return true when the argument is quoted.
070     */
071    public static boolean isQuoted(final String argument) {
072        return argument.startsWith(SINGLE_QUOTE) && argument.endsWith(SINGLE_QUOTE) || argument.startsWith(DOUBLE_QUOTE) && argument.endsWith(DOUBLE_QUOTE);
073    }
074
075    /**
076     * Put quotes around the given String if necessary.
077     * <p>
078     * If the argument doesn't include spaces or quotes, return it as is. If it contains double quotes, use single quotes - else surround the argument by double
079     * quotes.
080     * </p>
081     *
082     * @param argument the argument to be quoted.
083     * @return the quoted argument.
084     * @throws IllegalArgumentException If argument contains both types of quotes.
085     */
086    public static String quoteArgument(final String argument) {
087
088        String cleanedArgument = argument.trim();
089
090        // strip the quotes from both starts and ends
091        while (cleanedArgument.startsWith(SINGLE_QUOTE) && cleanedArgument.endsWith(SINGLE_QUOTE)) {
092            cleanedArgument = cleanedArgument.substring(1, cleanedArgument.length() - 1);
093        }
094
095        while (cleanedArgument.startsWith(DOUBLE_QUOTE) && cleanedArgument.endsWith(DOUBLE_QUOTE)) {
096            cleanedArgument = cleanedArgument.substring(1, cleanedArgument.length() - 1);
097        }
098
099        final StringBuilder buf = new StringBuilder();
100        if (cleanedArgument.contains(DOUBLE_QUOTE)) {
101            if (cleanedArgument.contains(SINGLE_QUOTE)) {
102                throw new IllegalArgumentException("Can't handle single and double quotes in same argument");
103            }
104            return buf.append(SINGLE_QUOTE).append(cleanedArgument).append(SINGLE_QUOTE).toString();
105        }
106        if (cleanedArgument.contains(SINGLE_QUOTE) || cleanedArgument.contains(" ")) {
107            return buf.append(DOUBLE_QUOTE).append(cleanedArgument).append(DOUBLE_QUOTE).toString();
108        }
109        return cleanedArgument;
110    }
111
112    /**
113     * Split a string into an array of strings based on a separator.
114     *
115     * @param input     what to split.
116     * @param splitChar what to split on.
117     * @return the array of strings.
118     */
119    public static String[] split(final String input, final String splitChar) {
120        final StringTokenizer tokens = new StringTokenizer(input, splitChar);
121        final List<String> strList = new ArrayList<>();
122        while (tokens.hasMoreTokens()) {
123            strList.add(tokens.nextToken());
124        }
125        return strList.toArray(EMPTY_STRING_ARRAY);
126    }
127
128    /**
129     * Perform a series of substitutions.
130     * <p>
131     * The substitutions are performed by replacing ${variable} in the target string with the value of provided by the key "variable" in the provided hash
132     * table.
133     * </p>
134     * <p>
135     * A key consists of the following characters:
136     * </p>
137     * <ul>
138     * <li>letter
139     * <li>digit
140     * <li>dot character
141     * <li>hyphen character
142     * <li>plus character
143     * <li>underscore character
144     * </ul>
145     *
146     * @param argStr    the argument string to be processed.
147     * @param vars      name/value pairs used for substitution.
148     * @param isLenient ignore a key not found in vars or throw a RuntimeException?
149     * @return String target string with replacements.
150     */
151    public static StringBuffer stringSubstitution(final String argStr, final Map<? super String, ?> vars, final boolean isLenient) {
152
153        final StringBuffer argBuf = new StringBuffer();
154
155        if (argStr == null || argStr.isEmpty()) {
156            return argBuf;
157        }
158
159        if (vars == null || vars.isEmpty()) {
160            return argBuf.append(argStr);
161        }
162
163        final int argStrLength = argStr.length();
164
165        for (int cIdx = 0; cIdx < argStrLength;) {
166
167            char ch = argStr.charAt(cIdx);
168            char del = ' ';
169
170            switch (ch) {
171
172            case '$':
173                final StringBuilder nameBuf = new StringBuilder();
174                del = argStr.charAt(cIdx + 1);
175                if (del == '{') {
176                    cIdx++;
177
178                    for (++cIdx; cIdx < argStr.length(); ++cIdx) {
179                        ch = argStr.charAt(cIdx);
180                        if (ch != '_' && ch != '.' && ch != '-' && ch != '+' && !Character.isLetterOrDigit(ch)) {
181                            break;
182                        }
183                        nameBuf.append(ch);
184                    }
185
186                    if (nameBuf.length() >= 0) {
187
188                        String value;
189                        final Object temp = vars.get(nameBuf.toString());
190
191                        if (temp instanceof File) {
192                            // for a file we have to fix the separator chars to allow
193                            // cross-platform compatibility
194                            value = fixFileSeparatorChar(((File) temp).getAbsolutePath());
195                        } else {
196                            value = Objects.toString(temp, null);
197                        }
198
199                        if (value != null) {
200                            argBuf.append(value);
201                        } else {
202                            if (!isLenient) {
203                                // complain that no variable was found
204                                throw new IllegalArgumentException("No value found for : " + nameBuf);
205                            }
206                            // just append the unresolved variable declaration
207                            argBuf.append("${").append(nameBuf.toString()).append("}");
208                        }
209
210                        del = argStr.charAt(cIdx);
211
212                        if (del != '}') {
213                            throw new IllegalArgumentException("Delimiter not found for : " + nameBuf);
214                        }
215                    }
216                } else {
217                    argBuf.append(ch);
218                }
219                cIdx++;
220
221                break;
222
223            default:
224                argBuf.append(ch);
225                ++cIdx;
226                break;
227            }
228        }
229
230        return argBuf;
231    }
232
233    /**
234     * Concatenates an array of string using a separator.
235     *
236     * @param strings   the strings to concatenate.
237     * @param separator the separator between two strings.
238     * @return the concatenated strings.
239     * @deprecated Use {@link String#join(CharSequence, CharSequence...)}.
240     */
241    @Deprecated
242    public static String toString(final String[] strings, final String separator) {
243        return String.join(separator, strings);
244    }
245
246    /**
247     * Constructs a new instance.
248     *
249     * @deprecated Will be private in the next major version.
250     */
251    @Deprecated
252    public StringUtils() {
253        // empty
254    }
255}