El verdadero poder de la función http_build_query de PHP es su capacidad para obtener una matriz asociativa y traducirla a la cadena URL. El siguiente código hace algo similar y permite que los parámetros de URL se construyan como un mapa de múltiples niveles que incluye mapas anidados y colecciones. Con algo más de trabajo, también se puede agregar un soporte para Array.
Los métodos de prueba se muestran a continuación.
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.*;
/**
* Class: URLBuilder
* User: Gilad Tiram
* Date: 6/12/13
* Time: 4:02 PM
* <p/>
* <p/>
* Utility that helps to build URL String
*/
public class URLBuilder {
/**
* Build URL string from Map of params. Nested Map and Collection is also supported
*
* @param params Map of params for constructing the URL Query String
* @param encoding encoding type. If not set the "UTF-8" is selected by default
* @return String of type key=value&...key=value
* @throws java.io.UnsupportedEncodingException
* if encoding isnot supported
*/
public static String httpBuildQuery(Map<String, Object> params, String encoding) {
if (isEmpty(encoding)) {
encoding = "UTF-8";
}
StringBuilder sb = new StringBuilder();
for (Map.Entry<String, Object> entry : params.entrySet()) {
if (sb.length() > 0) {
sb.append('&');
}
String name = entry.getKey();
Object value = entry.getValue();
if (value instanceof Map) {
List<String> baseParam = new ArrayList<String>();
baseParam.add(name);
String str = buildUrlFromMap(baseParam, (Map) value, encoding);
sb.append(str);
} else if (value instanceof Collection) {
List<String> baseParam = new ArrayList<String>();
baseParam.add(name);
String str = buildUrlFromCollection(baseParam, (Collection) value, encoding);
sb.append(str);
} else {
sb.append(encodeParam(name));
sb.append("=");
sb.append(encodeParam(value));
}
}
return sb.toString();
}
private static String buildUrlFromMap(List<String> baseParam, Map<Object, Object> map, String encoding) {
StringBuilder sb = new StringBuilder();
String token;
//Build string of first level - related with params of provided Map
for (Map.Entry<Object, Object> entry : map.entrySet()) {
if (sb.length() > 0) {
sb.append('&');
}
String name = String.valueOf(entry.getKey());
Object value = entry.getValue();
if (value instanceof Map) {
List<String> baseParam2 = new ArrayList<String>(baseParam);
baseParam2.add(name);
String str = buildUrlFromMap(baseParam2, (Map) value, encoding);
sb.append(str);
} else if (value instanceof List) {
List<String> baseParam2 = new ArrayList<String>(baseParam);
baseParam2.add(name);
String str = buildUrlFromCollection(baseParam2, (List) value, encoding);
sb.append(str);
} else {
token = getBaseParamString(baseParam) + "[" + name + "]=" + encodeParam(value);
sb.append(token);
}
}
return sb.toString();
}
private static String buildUrlFromCollection(List<String> baseParam, Collection coll, String encoding) {
StringBuilder sb = new StringBuilder();
String token;
if (!(coll instanceof List)) {
coll = new ArrayList(coll);
}
List arrColl = (List) coll;
//Build string of first level - related with params of provided Map
for (int i = 0; i < arrColl.size(); i++) {
if (sb.length() > 0) {
sb.append('&');
}
Object value = (Object) arrColl.get(i);
if (value instanceof Map) {
List<String> baseParam2 = new ArrayList<String>(baseParam);
baseParam2.add(String.valueOf(i));
String str = buildUrlFromMap(baseParam2, (Map) value, encoding);
sb.append(str);
} else if (value instanceof List) {
List<String> baseParam2 = new ArrayList<String>(baseParam);
baseParam2.add(String.valueOf(i));
String str = buildUrlFromCollection(baseParam2, (List) value, encoding);
sb.append(str);
} else {
token = getBaseParamString(baseParam) + "[" + i + "]=" + encodeParam(value);
sb.append(token);
}
}
return sb.toString();
}
private static String getBaseParamString(List<String> baseParam) {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < baseParam.size(); i++) {
String s = baseParam.get(i);
if (i == 0) {
sb.append(s);
} else {
sb.append("[" + s + "]");
}
}
return sb.toString();
}
/**
* Check if String is either empty or null
*
* @param str string to check
* @return true if string is empty. Else return false
*/
public static boolean isEmpty(String str) {
return str == null || str.length() == 0;
}
private static String encodeParam(Object param) {
try {
return URLEncoder.encode(String.valueOf(param), "UTF-8");
} catch (UnsupportedEncodingException e) {
return URLEncoder.encode(String.valueOf(param));
}
}
/* ========================================================================= */
/* Test functions */
/* ========================================================================= */
public static void main(String[] args) {
//basicTest();
//testWithMap();
//testWithList();
//testWithNestedMap();
//testWithNestedList();
testCompound();
}
private static void basicTest() {
Map<String, Object> params = new LinkedHashMap<String, Object>();
params.put("a", "1");
params.put("b", "2");
params.put("c", "3");
System.out.println(httpBuildQuery(params, "UTF-8"));
}
private static void testWithMap() {
Map<String, Object> params = new LinkedHashMap<String, Object>();
params.put("a", "1");
params.put("b", "2");
Map<String, Object> cParams = new LinkedHashMap<String, Object>();
cParams.put("c1", "c1val");
cParams.put("c2", "c2val");
params.put("c", cParams);
System.out.println(httpBuildQuery(params, "UTF-8"));
}
private static void testWithNestedMap() {
Map<String, Object> params = new LinkedHashMap<String, Object>();
params.put("a", "1");
params.put("b", "2");
Map<String, Object> cParamsLevel1 = new LinkedHashMap<String, Object>();
cParamsLevel1.put("cL1-1", "cLevel1-1val");
cParamsLevel1.put("cL1-2", "cLevel1-2val");
Map<String, Object> cParamsLevel2 = new LinkedHashMap<String, Object>();
cParamsLevel2.put("cL2-1", "cLevel2-1val");
cParamsLevel2.put("cL2-2", "cLevel2-2val");
cParamsLevel1.put("cL1-3", cParamsLevel2);
params.put("c", cParamsLevel1);
System.out.println(httpBuildQuery(params, "UTF-8"));
}
private static void testWithList() {
Map<String, Object> params = new LinkedHashMap<String, Object>();
params.put("a", "1");
params.put("b", "2");
List<Object> cParams = new ArrayList<Object>();
cParams.add("c1val");
cParams.add("c2val");
params.put("c", cParams);
System.out.println(httpBuildQuery(params, "UTF-8"));
}
private static void testWithNestedList() {
Map<String, Object> params = new LinkedHashMap<String, Object>();
params.put("a", "1");
params.put("b", "2");
List<Object> cParamsLevel1 = new ArrayList<Object>();
cParamsLevel1.add("cL1-val1");
cParamsLevel1.add("cL12-val2");
List<Object> cParamsLevel2 = new ArrayList<Object>();
cParamsLevel2.add("cL2-val1");
cParamsLevel2.add("cL2-val2");
cParamsLevel1.add(cParamsLevel2);
params.put("c", cParamsLevel1);
System.out.println(httpBuildQuery(params, "UTF-8"));
}
private static void testCompound() {
Map<String, Object> params = new LinkedHashMap<String, Object>();
//flat
params.put("a", "1");
params.put("b", "2");
//Map level 1
Map<String, Object> cParamsLevel1 = new LinkedHashMap<String, Object>();
cParamsLevel1.put("cL1-1", "cLevel1-1val");
cParamsLevel1.put("cL1-2", "cLevel1-2val");
//Map level 2
Map<String, Object> cParamsLevel2 = new LinkedHashMap<String, Object>();
cParamsLevel2.put("cL2-1", "cLevel2-1val");
cParamsLevel2.put("cL2-2", "cLevel2-2val");
cParamsLevel1.put("cL1-3", cParamsLevel2);
params.put("c", cParamsLevel1);
//List level 1
List<Object> dParamsLevel1 = new ArrayList<Object>();
dParamsLevel1.add("dL1-val1");
dParamsLevel1.add("dL12-val2");
//List level 2
List<Object> dParamsLevel2 = new ArrayList<Object>();
dParamsLevel2.add("dL2-val1");
dParamsLevel2.add("dL2-val2");
dParamsLevel1.add(dParamsLevel2);
params.put("d", dParamsLevel1);
System.out.println(httpBuildQuery(params, "UTF-8"));
}
}
Para facilitar la prueba de sus resultados añadir la cadena resultado de las pruebas como cadena de consulta de la URL real que apunte a esta PHP. Ejemplo
http://localhost/test.php?a=1&b=2&c[cL1-1]=cLevel1-1val&c[cL1-2]=cLevel1-2val&c[cL1-3][cL2-1]=cLevel2-1val&c[cL1-3][cL2-2]=cLevel2-2val&d[0]=dL1-val1&d[1]=dL12-val2&d[2][0]=dL2-val1&d[2][1]=dL2-val2
<?php
var_dump($_REQUEST);
?>
¿Está funcionando su código? ¿Dónde está el problema? ¿Cuál es la pregunta? –
Mi código funciona. Mi pregunta era si hay alguna clase o método que hace esto de una mejor manera. No me gusta reinventar la rueda si hay algo listo para eso que pueda tomar un mejor enfoque en el caso que mi código. – falmp