/* * Copyright (c) 1998, 2004, 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 sun.security.util; import java.net.URI;import java.net.URISyntaxException;import java.security.GeneralSecurityException; /** * A utility class to expand properties embedded in a string. * Strings of the form ${some.property.name} are expanded to * be the value of the property. Also, the special ${/} property * is expanded to be the same as file.separator. If a property * is not set, a GeneralSecurityException will be thrown. * * @author Roland Schemers */public class PropertyExpander {      public static class ExpandException extends GeneralSecurityException {         private static final long serialVersionUID = -7941948581406161702L;         public ExpandException(String msg) {            super(msg);        }    }     public static String expand(String value)        throws ExpandException    {        return expand(value, false);    }      public static String expand(String value, boolean encodeURL)         throws ExpandException     {        if (value == null)            return null;         int p = value.indexOf("${", 0);         // no special characters        if (p == -1) return value;         StringBuffer sb = new StringBuffer(value.length());        int max = value.length();        int i = 0;  // index of last character we copied     scanner:        while (p < max) {            if (p > i) {                // copy in anything before the special stuff                sb.append(value.substring(i, p));                i = p;            }            int pe = p+2;             // do not expand ${{ ... }}            if (pe < max && value.charAt(pe) == '{') {                pe = value.indexOf("}}", pe);                if (pe == -1 || pe+2 == max) {                    // append remaining chars                    sb.append(value.substring(p));                    break scanner;                } else {                    // append as normal text                    pe++;                    sb.append(value.substring(p, pe+1));                }            } else {                while ((pe < max) && (value.charAt(pe) != '}')) {                    pe++;                }                if (pe == max) {                    // no matching '}' found, just add in as normal text                    sb.append(value.substring(p, pe));                    break scanner;                }                String prop = value.substring(p+2, pe);                if (prop.equals("/")) {                    sb.append(java.io.File.separatorChar);                } else {                    String val = System.getProperty(prop);                    if (val != null) {                        if (encodeURL) {                            // encode 'val' unless it's an absolute URI                            // at the beginning of the string buffer                            try {                                if (sb.length() > 0 ||                                    !(new URI(val)).isAbsolute()) {                                    val = sun.net.www.ParseUtil.encodePath(val);                                }                            } catch (URISyntaxException use) {                                val = sun.net.www.ParseUtil.encodePath(val);                            }                        }                        sb.append(val);                    } else {                        throw new ExpandException(                                             "unable to expand property " +                                             prop);                    }                }            }            i = pe+1;            p = value.indexOf("${", i);            if (p == -1) {                // no more to expand. copy in any extra                if (i < max) {                    sb.append(value.substring(i, max));                }                // break out of loop                break scanner;            }        }        return sb.toString();    }}