simple.common.FeatureList Maven / Gradle / Ivy
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package simple.common;
import java.util.HashMap;
/**
* A list of [enabled] features.
*/
public class FeatureList {
private HashMap list;
/**
* Create a list of [enabled] features.
*/
public FeatureList() {
list = new HashMap();
}
//
// FeatureList
//
/**
* Clear the list of features.
*/
public void clear() {
getList().clear();
}
/**
* Read an encoded features list.
*
* Encoded features are in the form of:
* name[=value][:name[=value]...]
*/
public void decode(String encoded) {
int len;
int pos;
int epos;
int cpos;
String name;
String value;
getList().clear();
len = encoded.length();
pos = 0;
while (pos < len) {
if ((cpos = encoded.indexOf(':', pos)) == -1) {
cpos = len;
}
if (((epos = encoded.indexOf('=', pos)) == -1) || (epos > cpos)) {
epos = cpos;
}
name = encoded.substring(pos, epos);
if (epos < cpos) {
value = encoded.substring(epos + 1, cpos);
} else {
value = "";
}
getList().put(name, value);
pos = cpos + 1;
}
}
/**
* Build an encoded features list.
*
* Encoded features are in the form of:
* name[=value][:name[=value]...]
*/
public String encode() {
StringBuffer sbuf;
sbuf = new StringBuffer();
for (String name : getList().keySet()) {
String value = getList().get(name);
if (sbuf.length() != 0) {
sbuf.append(':');
}
sbuf.append(name);
if (value.length() != 0) {
sbuf.append('=');
sbuf.append(value);
}
}
return sbuf.toString();
}
/**
* Get a feature value.
*
* @return A feature value, or null if not-enabled.
*/
public String get(String name) {
return getList().get(name);
}
/**
* Determine if a feature is enabled.
*
* @return true is a feature is enabled.
*/
public boolean has(String name) {
return getList().containsKey(name);
}
/**
* Enable/disable a feature.
*
* @param name
* The feature mnemonic.
* @param enabled
* Flag indicating if enabled.
*
* @return true if the list changed,
* false otherwise.
*/
public boolean set(String name, boolean enabled) {
return set(name, enabled ? "" : null);
}
/**
* Set/remove a feature. NOTE: The names and values MUST NOT contain
* = (equals), or : (colon).
*
* @param name
* The feature mnemonic.
* @param value
* The feature value, or null to disable.
*
* @return true if the list changed,
* false otherwise.
*/
public boolean set(String name, String value) {
if (value != null) {
getList().put(name, value);
} else {
if (getList().remove(name) == null) {
return false;
}
}
return true;
}
public HashMap getList() {
return list;
}
}