URLConnections - Java Network Programming - page 201

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Example 7-6 is a simple Java class for parsing and querying Cache-control headers.
Example 7-6. How to inspect a Cache-control header
import java.util.Date ;
import java.util.Locale ;
public class CacheControl {
private Date maxAge = null ;
private Date sMaxAge = null ;
private boolean mustRevalidate = false ;
private boolean noCache = false ;
private boolean noStore = false ;
private boolean proxyRevalidate = false ;
private boolean publicCache = false ;
private boolean privateCache = false ;
public CacheControl ( String s ) {
if ( s == null || ! s . contains ( ":" )) {
return ; // default policy
}
String value = s . split ( ":" )[ 1 ]. trim ();
String [] components = value . split ( "," );
Date now = new Date ();
for ( String component : components ) {
try {
component = component . trim (). toLowerCase ( Locale . US );
if ( component . startsWith ( "max-age=" )) {
int secondsInTheFuture = Integer . parseInt ( component . substring ( 8 ));
maxAge = new Date ( now . getTime () + 1000 * secondsInTheFuture );
} else if ( component . startsWith ( "s-maxage=" )) {
int secondsInTheFuture = Integer . parseInt ( component . substring ( 8 ));
sMaxAge = new Date ( now . getTime () + 1000 * secondsInTheFuture );
} else if ( component . equals ( "must-revalidate" )) {
mustRevalidate = true ;
} else if ( component . equals ( "proxy-revalidate" )) {
proxyRevalidate = true ;
} else if ( component . equals ( "no-cache" )) {
noCache = true ;
} else if ( component . equals ( "public" )) {
publicCache = true ;
} else if ( component . equals ( "private" )) {
privateCache = true ;