Java tutorial
/* * Copyright (C) 2010 ZXing 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 com.joyepay.qrcode.result.supplement; import android.content.Context; import android.os.Handler; import android.text.Spannable; import android.text.SpannableString; import android.text.Spanned; import android.text.method.LinkMovementMethod; import android.text.style.URLSpan; import android.widget.TextView; import com.google.zxing.client.result.ISBNParsedResult; import com.google.zxing.client.result.ParsedResult; import com.google.zxing.client.result.ProductParsedResult; import com.google.zxing.client.result.URIParsedResult; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.client.methods.HttpGet; import org.apache.http.client.methods.HttpUriRequest; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.UnsupportedEncodingException; import java.lang.ref.WeakReference; import java.util.ArrayList; import java.util.Collection; import java.util.concurrent.Callable; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; import java.util.concurrent.ThreadFactory; import java.util.concurrent.TimeUnit; public abstract class SupplementalInfoRetriever implements Callable<Void> { private static ExecutorService executorInstance = null; private static synchronized ExecutorService getExecutorService() { if (executorInstance == null) { executorInstance = Executors.newCachedThreadPool(new ThreadFactory() { public Thread newThread(Runnable r) { Thread t = new Thread(r); t.setDaemon(true); return t; } }); } return executorInstance; } public static void maybeInvokeRetrieval(TextView textView, ParsedResult result, Handler handler, // HistoryManager historyManager, Context context) { Collection<SupplementalInfoRetriever> retrievers = new ArrayList<SupplementalInfoRetriever>(1); // if (result instanceof URIParsedResult) { // retrievers.add(new URIResultInfoRetriever(textView, (URIParsedResult) result, handler, historyManager, context)); // } else if (result instanceof ProductParsedResult) { // String productID = ((ProductParsedResult) result).getProductID(); // retrievers.add(new ProductResultInfoRetriever(textView, productID, handler, historyManager, context)); // } else if (result instanceof ISBNParsedResult) { // String isbn = ((ISBNParsedResult) result).getISBN(); // retrievers.add(new ProductResultInfoRetriever(textView, isbn, handler, historyManager, context)); // retrievers.add(new BookResultInfoRetriever(textView, isbn, handler, historyManager, context)); // } // // for (SupplementalInfoRetriever retriever : retrievers) { // ExecutorService executor = getExecutorService(); // Future<?> future = executor.submit(retriever); // // Make sure it's interrupted after a short time though // executor.submit(new KillerCallable(future, 10, TimeUnit.SECONDS)); // } } private final WeakReference<TextView> textViewRef; private final Handler handler; // private final HistoryManager historyManager; SupplementalInfoRetriever(TextView textView, Handler handler // ,HistoryManager historyManager ) { this.textViewRef = new WeakReference<TextView>(textView); this.handler = handler; // this.historyManager = historyManager; } public final Void call() throws IOException, InterruptedException { retrieveSupplementalInfo(); return null; } abstract void retrieveSupplementalInfo() throws IOException, InterruptedException; final void append(String itemID, String source, String[] newTexts, String linkURL) throws InterruptedException { final TextView textView = textViewRef.get(); if (textView == null) { throw new InterruptedException(); } StringBuilder newTextCombined = new StringBuilder(); if (source != null) { newTextCombined.append(source).append(" : "); } int linkStart = newTextCombined.length(); boolean first = true; for (String newText : newTexts) { if (first) { newTextCombined.append(newText); first = false; } else { newTextCombined.append(" ["); newTextCombined.append(newText); newTextCombined.append(']'); } } int linkEnd = newTextCombined.length(); String newText = newTextCombined.toString(); final Spannable content = new SpannableString(newText + "\n\n"); if (linkURL != null) { content.setSpan(new URLSpan(linkURL), linkStart, linkEnd, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE); } handler.post(new Runnable() { public void run() { textView.append(content); textView.setMovementMethod(LinkMovementMethod.getInstance()); } }); // Add the text to the history. // historyManager.addHistoryItemDetails(itemID, newText); } // protected static String downloadViaHttp(String uri) throws IOException { // HttpUriRequest get = new HttpGet(uri); // AndroidHttpClient client = AndroidHttpClient.newInstance(null); // HttpResponse response = client.execute(get); // int status = response.getStatusLine().getStatusCode(); // if (status != 200) { // throw new IOException(); // } // return consume(response.getEntity()); // } private static String consume(HttpEntity entity) throws IOException { ByteArrayOutputStream out = new ByteArrayOutputStream(); InputStream in = null; try { in = entity.getContent(); byte[] buffer = new byte[1024]; int bytesRead; while ((bytesRead = in.read(buffer)) > 0) { out.write(buffer, 0, bytesRead); } } finally { if (in != null) { try { in.close(); } catch (IOException ioe) { // continue } } } try { return new String(out.toByteArray(), "UTF-8"); } catch (UnsupportedEncodingException uee) { // can't happen throw new IllegalStateException(uee); } } }