/**
* Sencha GXT 3.0.0 - Sencha for GWT
* Copyright(c) 2007-2012, Sencha, Inc.
* licensing@sencha.com
*
* http://www.sencha.com/products/gxt/license/
*/
package com.sencha.gxt.data.client.writer;
import java.util.Collection;
import com.google.gwt.http.client.URL;
import com.google.web.bindery.autobean.shared.AutoBean;
import com.google.web.bindery.autobean.shared.AutoBeanFactory;
import com.google.web.bindery.autobean.shared.AutoBeanUtils;
import com.google.web.bindery.autobean.shared.AutoBeanVisitor;
import com.sencha.gxt.data.shared.writer.AutoBeanWriter;
/**
* Encodes an object into a format that can be used for a GET query string or a
* POST url-encoded body.
*
* @param <M> the starting data format for the model to be inputed
*/
public class UrlEncodingWriter<M> extends AutoBeanWriter<M, String> {
/**
* A URL Encoding Appender provides support for appending a field and value to
* a URL encoded value. Instances of this type can be passed to
* {@link #appendModel}.
*/
public interface UrlEncodingAppender {
/**
* Append the given field and value to an encapsulated URL encoded value,
* creating or updating it as necessary.
*
* @param field the field to append
* @param value the value to append
* @return the URL encoding appender
*/
UrlEncodingAppender append(String field, String value);
}
/**
* Creates a new URL encoding writing that can format an object into a GET
* query string or POST url-encoded body.
*
* @param factory an auto bean factory that can decode objects of type M
* @param clazz the class to write
*/
public UrlEncodingWriter(AutoBeanFactory factory, Class<M> clazz) {
super(factory, clazz);
}
/**
* Appends all of the relevant pieces of data to the url data.
*
* @param model the model
* @param appender the url encoding appender
*/
public void appendModel(M model, final UrlEncodingAppender appender) {
AutoBean<M> autoBean = getAutoBean(model);
autoBean.accept(new AutoBeanVisitor() {
@Override
public boolean visitCollectionProperty(String propertyName, AutoBean<Collection<?>> value,
CollectionPropertyContext ctx) {
if (value != null) {
for (Object obj : value.as()) {
AutoBean<?> subBean = AutoBeanUtils.getAutoBean(obj);
subBean.accept(this);
}
}
return false;
}
@Override
public boolean visitValueProperty(String propertyName, Object value, PropertyContext ctx) {
if (value != null) {
appender.append(propertyName, value.toString());
}
return false;
}
});
}
@Override
public String write(M model) {
final StringBuilder sb = new StringBuilder();
UrlEncodingAppender a = new UrlEncodingAppender() {
boolean first = true;
@Override
public UrlEncodingAppender append(String field, String value) {
if (!first) {
sb.append("&");
}
first = false;
sb.append(URL.encodeQueryString(field)).append("=").append(URL.encodeQueryString(value));
return this;
}
};
appendModel(model, a);
return sb.toString();
}
}