/*
* Ext GWT - Ext for GWT
* Copyright(c) 2007, 2008, Ext JS, LLC.
* licensing@extjs.com
*
* http://extjs.com/license
*/
package com.extjs.gxt.ui.client.state;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import com.extjs.gxt.ui.client.Events;
import com.extjs.gxt.ui.client.event.BaseObservable;
import com.extjs.gxt.ui.client.event.StateEvent;
/**
* Abstract base class for state provider implementations. This class provides
* methods for encoding and decoding objects.
*/
public abstract class Provider extends BaseObservable {
protected StateManager manager;
protected void bind(StateManager manager) {
this.manager = manager;
}
/**
* Clears a value.
*
* @param name the key name
*/
public void clear(String name) {
clearKey(name);
StateEvent se = new StateEvent(manager);
se.name = name;
fireEvent(Events.StateChange, se);
}
/**
* Returns the current value for a key.
*
* @param name the key name
* @return the value
*/
public Object get(String name) {
String val = getValue(name);
if (val == null) return null;
Object obj = decodeValue(val);
return obj;
}
public Map<String, Object> getMap(String name) {
String val = getValue(name);
if (val == null) return null;
Map map = (Map) decodeValue(val);
return map;
}
/**
* Returns the current value for a key.
*
* @param name the key name
* @return the value
*/
public String getString(String name) {
String val = getValue(name);
if (val == null) return null;
String obj = (String) decodeValue(val);
return obj;
}
/**
* Returns the current value for a key.
*
* @param name the key name
* @return the value
*/
public boolean getBoolean(String name) {
String val = getValue(name);
if (val == null) return false;
Boolean bVal = (Boolean) decodeValue(val);
return bVal.booleanValue();
}
/**
* Returns the current value for a key.
*
* @param name the key name
* @return the value
*/
public Date getDate(String name) {
String val = getValue(name);
if (val == null) return null;
Date date = (Date) decodeValue(val);
return date;
}
/**
* Returns the current value for a key.
*
* @param name the key name
* @return the value or -1
*/
public int getInteger(String name) {
String val = getValue(name);
Integer iVal = (Integer) decodeValue(val);
if (iVal == null) {
return -1;
}
return iVal.intValue();
}
/**
* Sets a key.
*
* @param name the key name
* @param value the value
*/
public void set(String name, Object value) {
String val = encodeValue(value);
setValue(name, val);
StateEvent re = new StateEvent(manager, name, value);
re.name = name;
re.value = value;
fireEvent(Events.StateChange, re);
}
protected abstract void clearKey(String name);
protected Map<String, Object> decodeMap(String value) {
Map<String, Object> map = new HashMap<String, Object>();
String vals = value.substring(2);
String[] values = vals.split(",");
for (String s : values) {
String key = s.substring(0, s.indexOf("|"));
Object val = decodeValue(s.substring(s.indexOf("|") + 1));
map.put(key, val);
}
return map;
}
protected Object decodeValue(String value) {
try {
if (value == null || value.length() < 3) {
return null;
}
String type = value.substring(0, 2);
String val = value.substring(2);
if (type.equals("m:")) {
return decodeMap(value);
} else if (type.equals("i:")) {
return Integer.decode(val);
} else if (type.equals("d:")) {
long time = Long.parseLong(val);
return new Date(time);
} else if (type.equals("f:")) {
return new Float(val);
} else if (type.equals("b:")) {
return new Boolean(val);
}
return val;
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
protected String encodeMap(Map<String, Object> map) {
StringBuffer sb = new StringBuffer();
sb.append("m:");
for (String key : map.keySet()) {
String val = encodeValue(map.get(key));
sb.append(key + "|" + val + ",");
}
int end = sb.length() - (sb.length() > 2 ? 1 : 0);
String encode = sb.toString().substring(0, end);
return encode;
}
protected String encodeValue(Object value) {
if (value instanceof Map) {
return encodeMap((Map) value);
} else if (value instanceof Date) {
return "d:" + ((Date) value).getTime();
} else if (value instanceof Integer) {
return "i:" + value;
} else if (value instanceof Float) {
return "f:" + value;
} else if (value instanceof Boolean) {
return "b:" + value;
}
return "s:" + value.toString();
}
protected abstract String getValue(String name);
protected abstract void setValue(String name, String value);
}