package org.cruxframework.crux.core.server.rest.util.header;
import java.util.List;
import org.cruxframework.crux.core.server.rest.core.CacheControl;
/**
* @author <a href="mailto:bill@burkecentral.com">Bill Burke</a>
* @version $Revision: 1 $
*/
public class CacheControlHeaderParser
{
public static CacheControl fromString(String value) throws IllegalArgumentException
{
if (value == null) throw new IllegalArgumentException("Cache-Control value is null");
CacheControl result = new CacheControl();
String[] directives = value.split(",");
for (String directive : directives)
{
directive = directive.trim();
String[] nv = directive.split("=");
String name = nv[0].trim();
String val = null;
if (nv.length > 1)
{
val = nv[1].trim();
if (val.startsWith("\"")) val = val.substring(1);
if (val.endsWith("\"")) val = val.substring(0, val.length() - 1);
}
String lowercase = name.toLowerCase();
if ("no-cache".equals(lowercase))
{
result.setNoCache(true);
if (val != null && !"".equals(val))
{
result.getNoCacheFields().add(val);
}
}
else if ("private".equals(lowercase))
{
result.setPrivate(true);
if (val != null && !"".equals(val))
{
result.getPrivateFields().add(val);
}
}
else if ("no-store".equals(lowercase))
{
result.setNoStore(true);
}
else if ("max-age".equals(lowercase))
{
if (val == null)
throw new IllegalArgumentException("CacheControl max-age header does not have a value: " + value);
result.setMaxAge(Integer.valueOf(val));
}
else if ("s-maxage".equals(lowercase))
{
if (val == null)
throw new IllegalArgumentException("CacheControl s-maxage header does not have a value: " + value);
result.setSMaxAge(Integer.valueOf(val));
}
else if ("no-transform".equals(lowercase))
{
result.setNoTransform(true);
}
else if ("must-revalidate".equals(lowercase))
{
result.setMustRevalidate(true);
}
else if ("proxy-revalidate".equals(lowercase))
{
result.setProxyRevalidate(true);
}
else if ("public".equals(lowercase))
{
result.setPublic(true);
}
else
{
if (val == null) val = "";
result.getCacheExtension().put(name, val);
}
}
return result;
}
private static StringBuffer addDirective(String directive, StringBuffer buffer)
{
if (buffer.length() > 0) buffer.append(", ");
buffer.append(directive);
return buffer;
}
public static String toString(CacheControl value)
{
StringBuffer buffer = new StringBuffer();
if (value.isNoCache())
{
List<String> fields = value.getNoCacheFields();
if (fields.size() < 1)
{
addDirective("no-cache", buffer);
}
else
{
for (String field : value.getNoCacheFields())
{
addDirective("no-cache", buffer).append("=\"").append(field).append("\"");
}
}
}
if (value.isPublic())
{
addDirective("public", buffer);
}
if (value.isMustRevalidate()) addDirective("must-revalidate", buffer);
if (value.isNoTransform()) addDirective("no-transform", buffer);
if (value.isNoStore()) addDirective("no-store", buffer);
if (value.isProxyRevalidate()) addDirective("proxy-revalidate", buffer);
if (value.getSMaxAge() > -1) addDirective("s-maxage", buffer).append("=").append(value.getSMaxAge());
if (value.getMaxAge() > -1) addDirective("max-age", buffer).append("=").append(value.getMaxAge());
if (value.isPrivate())
{
List<String> fields = value.getPrivateFields();
if (fields.size() < 1) addDirective("private", buffer);
else
{
for (String field : value.getPrivateFields())
{
addDirective("private", buffer).append("=\"").append(field).append("\"");
}
}
}
for (String key : value.getCacheExtension().keySet())
{
String val = value.getCacheExtension().get(key);
addDirective(key, buffer);
if (val != null && !"".equals(val))
{
buffer.append("=\"").append(val).append("\"");
}
}
return buffer.toString();
}
}