/*
* 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
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*/
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();
}
}