/*
* Copyright 2015 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.social.support;
import java.io.UnsupportedEncodingException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URLEncoder;
import java.util.Iterator;
import java.util.List;
import java.util.Map.Entry;
import java.util.Set;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
/**
* Builds up a URI from individual URI components. Ensures that query parameters are application/x-www-form-urlencoded.
* @author Craig Walls
*/
public class URIBuilder {
private final String baseUri;
private MultiValueMap<String, String> parameters;
private URIBuilder(String baseUri) {
this.baseUri = baseUri;
parameters = new LinkedMultiValueMap<String, String>();
}
/**
* Creates a URIBuilder with a base URI string as the starting point
* @param baseUri a String URI to use as a starting point for the builder
* @return the URIBuilder
*/
public static URIBuilder fromUri(String baseUri) {
return new URIBuilder(baseUri);
}
/**
* Creates a URIBuilder with a base URI string as the starting point
* @param baseUri a URI to use as a starting point for the builder
* @return the URIBuilder
*/
public static URIBuilder fromUri(URI baseUri) {
return new URIBuilder(baseUri.toString());
}
/**
* Adds a query parameter to the URI
* @param name the parameter name
* @param value the parameter value
* @return the URIBuilder
*/
public URIBuilder queryParam(String name, String value) {
parameters.add(name, value);
return this;
}
/**
* Adds a query parameters to the URI
* @param params a Map of parameters to add the the URI
* @return the URIBuilder
*/
public URIBuilder queryParams(MultiValueMap<String, String> params) {
parameters.putAll(params);
return this;
}
/**
* Builds the URI
* @return the URI
*/
public URI build() {
try {
StringBuilder builder = new StringBuilder();
Set<Entry<String, List<String>>> entrySet = parameters.entrySet();
for (Iterator<Entry<String, List<String>>> entryIt = entrySet.iterator(); entryIt.hasNext();) {
Entry<String, List<String>> entry = entryIt.next();
String name = entry.getKey();
List<String> values = entry.getValue();
for(Iterator<String> valueIt = values.iterator(); valueIt.hasNext();) {
String value = valueIt.next();
builder.append(formEncode(name)).append("=");
if(value != null) {
builder.append(formEncode(value));
}
if(valueIt.hasNext()) {
builder.append("&");
}
}
if(entryIt.hasNext()) {
builder.append("&");
}
}
String queryDelimiter = "?";
if(URI.create(baseUri).getQuery() != null) {
queryDelimiter = "&";
}
return new URI(baseUri + (builder.length() > 0 ? queryDelimiter + builder.toString() : ""));
} catch (URISyntaxException e) {
throw new URIBuilderException("Unable to build URI: Bad URI syntax", e);
}
}
private String formEncode(String data) {
try {
return URLEncoder.encode(data, "UTF-8");
}
catch (UnsupportedEncodingException wontHappen) {
throw new IllegalStateException(wontHappen);
}
}
}