Java tutorial
/* * Copyright 2011 Alibaba.com All right reserved. This software is the * confidential and proprietary information of Alibaba.com ("Confidential * Information"). You shall not disclose such Confidential Information and shall * use it only in accordance with the terms of the license agreement you entered * into with Alibaba.com. */ package org.lansir.beautifulgirls.proxy; import java.io.File; import java.io.IOException; import java.io.UnsupportedEncodingException; import java.lang.annotation.Annotation; import java.lang.reflect.InvocationHandler; import java.lang.reflect.Method; import java.lang.reflect.Proxy; import java.net.URLEncoder; import java.util.ArrayList; import java.util.HashMap; import java.util.Iterator; import java.util.Map; import java.util.Map.Entry; import java.util.regex.Matcher; import java.util.regex.Pattern; import org.apache.http.NameValuePair; import org.apache.http.message.BasicNameValuePair; import org.lansir.beautifulgirls.annotation.AkAPI; import org.lansir.beautifulgirls.annotation.AkGET; import org.lansir.beautifulgirls.annotation.AkPOST; import org.lansir.beautifulgirls.annotation.AkParam; import org.lansir.beautifulgirls.annotation.AkSignature; import org.lansir.beautifulgirls.exception.AkException; import org.lansir.beautifulgirls.exception.AkInvokeException; import org.lansir.beautifulgirls.exception.AkServerStatusException; import org.lansir.beautifulgirls.network.HttpInvoker; import org.lansir.beautifulgirls.utils.JsonMapper; import android.util.Log; /** * Dynamic Proxy Invocation Handler * @author zhe.yangz 2011-12-28 ?04:47:56 */ public class ProxyInvocationHandler implements InvocationHandler { private static final String TAG = "ProxyInvocationHandler"; public Object bind(Class<?> clazz) { Class<?>[] clazzs = { clazz }; Object newProxyInstance = Proxy.newProxyInstance(clazz.getClassLoader(), clazzs, this); return newProxyInstance; } /** * Dynamic proxy invoke */ public Object invoke(Object proxy, Method method, Object[] args) throws AkInvokeException, AkServerStatusException, AkException, Exception { AkPOST akPost = method.getAnnotation(AkPOST.class); AkGET akGet = method.getAnnotation(AkGET.class); AkAPI akApi = method.getAnnotation(AkAPI.class); Annotation[][] annosArr = method.getParameterAnnotations(); String invokeUrl = akApi.url(); ArrayList<NameValuePair> params = new ArrayList<NameValuePair>(); // AkApiParams to hashmap, filter out of null-value HashMap<String, File> filesToSend = new HashMap<String, File>(); HashMap<String, String> paramsMapOri = new HashMap<String, String>(); HashMap<String, String> paramsMap = getRawApiParams2HashMap(annosArr, args, filesToSend, paramsMapOri); // Record this invocation ApiInvokeInfo apiInvokeInfo = new ApiInvokeInfo(); apiInvokeInfo.apiName = method.getName(); apiInvokeInfo.paramsMap.putAll(paramsMap); apiInvokeInfo.url = invokeUrl; // parse '{}'s in url invokeUrl = parseUrlbyParams(invokeUrl, paramsMap); // cleared hashmap to params, and filter out of the null value Iterator<Entry<String, String>> iter = paramsMap.entrySet().iterator(); while (iter.hasNext()) { Entry<String, String> entry = iter.next(); params.add(new BasicNameValuePair(entry.getKey(), entry.getValue())); } // get the signature string if using AkSignature akSig = method.getAnnotation(AkSignature.class); if (akSig != null) { Class<?> clazzSignature = akSig.using(); if (clazzSignature.getInterfaces().length > 0 // TODO: NEED VERIFY WHEN I HAVE TIME && InvokeSignature.class.getName().equals(clazzSignature.getInterfaces()[0].getName())) { InvokeSignature is = (InvokeSignature) clazzSignature.getConstructors()[0].newInstance(); String sigValue = is.signature(akSig, invokeUrl, params, paramsMapOri); String sigParamName = is.getSignatureParamName(); if (sigValue != null && sigParamName != null && sigValue.length() > 0 && sigParamName.length() > 0) { params.add(new BasicNameValuePair(sigParamName, sigValue)); } } } // choose POST GET PUT DELETE to use for this invoke String retString = ""; if (akGet != null) { StringBuilder sbUrl = new StringBuilder(invokeUrl); if (!(invokeUrl.endsWith("?") || invokeUrl.endsWith("&"))) { sbUrl.append("?"); } for (NameValuePair nvp : params) { sbUrl.append(nvp.getName()); sbUrl.append("="); sbUrl.append(nvp.getValue()); sbUrl.append("&"); } // now default using UTF-8, maybe improved later retString = HttpInvoker.get(sbUrl.toString()); } else if (akPost != null) { if (filesToSend.isEmpty()) { retString = HttpInvoker.post(invokeUrl, params); } else { retString = HttpInvoker.postWithFilesUsingURLConnection(invokeUrl, params, filesToSend); } } else { // use POST for default retString = HttpInvoker.post(invokeUrl, params); } // invoked, then add to history //ApiStats.addApiInvocation(apiInvokeInfo); //Log.d(TAG, retString); // parse the return-string Class<?> returnType = method.getReturnType(); try { if (String.class.equals(returnType)) { // the result return raw string return retString; } else { // return object using json decode return JsonMapper.json2pojo(retString, returnType); } } catch (IOException e) { throw new AkInvokeException(AkInvokeException.CODE_IO_EXCEPTION, e.getMessage(), e); } /* * also can use gson like this eg. * Gson gson = new Gson(); * return gson.fromJson(HttpInvoker.post(url, params), returnType); */ } /** * Replace all the {} block in url to the actual params, * clear the params used in {block}, return cleared params HashMap and replaced url. * @param url such as http://server/{namespace}/1/do * @param params such as hashmap include (namespace->'mobile') * @return the parsed param will be removed in HashMap (params) */ private String parseUrlbyParams(String url, HashMap<String, String> params) throws AkInvokeException { StringBuffer sbUrl = new StringBuffer(); Pattern pattern = Pattern.compile("\\{(.+?)\\}"); Matcher matcher = pattern.matcher(url); while (matcher.find()) { String paramValue = params.get(matcher.group(1)); if (paramValue != null) { matcher.appendReplacement(sbUrl, paramValue); } else { // {name}? throw new AkInvokeException(AkInvokeException.CODE_PARAM_IN_URL_NOT_FOUND, "Parameter {" + matcher.group(1) + "}'s value not found of url " + url + "."); } params.remove(matcher.group(1)); } matcher.appendTail(sbUrl); return sbUrl.toString(); } /** * AkApiParams to hashmap, filter out of null-value * * @param annosArr Method's params' annotation array[][] * @param args Method's params' values * @param filesToSend * @return HashMap all (paramName -> paramValue) */ private HashMap<String, String> getRawApiParams2HashMap(Annotation[][] annosArr, Object[] args, HashMap<String, File> filesToSend, HashMap<String, String> paramsMapOri) { HashMap<String, String> paramsMap = new HashMap<String, String>(); for (int idx = 0; idx < args.length; idx++) { String paramName = null; String encode = "none"; for (Annotation a : annosArr[idx]) { if (AkParam.class.equals(a.annotationType())) { AkParam ap = (AkParam) a; paramName = ap.value(); encode = ap.encode(); } } if (paramName != null) { Object arg = args[idx]; if (arg != null) { // filter out of null-value param if (encode != null && !"none".equals(encode)) { try { paramsMap.put(paramName, URLEncoder.encode(arg.toString(), encode)); } catch (UnsupportedEncodingException e) { Log.w(TAG, "UnsupportedEncodingException:" + encode); paramsMap.put(paramName, arg.toString()); } paramsMapOri.put(paramName, arg.toString()); } else if ("$paramMap".equals(paramName)) { Map<String, String> paramMap = (Map<String, String>) arg; paramsMap.putAll(paramMap); paramsMapOri.putAll(paramMap); } else if ("$filesToSend".equals(paramName)) { if (arg instanceof Map) { Map<String, File> files = (Map<String, File>) arg; filesToSend.putAll(files); } } else { paramsMap.put(paramName, arg.toString()); paramsMapOri.put(paramName, arg.toString()); } } } } return paramsMap; } }