post > 1024 byte is good

[GoogleCodeExporter]

/**
 * Translate.java
 *
 * Copyright (C) 2007,  Richard Midwinter
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, 
USA.
 */
package com.google.api.translate;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLEncoder;

/**
 * Makes the Google Translate API available to Java applications.
 * 
 * @author Richard Midwinter
 * @author Emeric Vernat
 * @author Juan B Cabral,chinese xiatianQQ11602011
 */
public class Translate {

    private static final String ENCODING = "UTF-8";
    private static final String INTERMEDIATE_LANGUAGE = Language.ENGLISH;
    private static final String URL_STRING 
= "http://translate.google.com/translate_t?langpair=";
    private static final String TEXT_VAR = "&text=";
    private static final int RATE_DELAY = 10; // 以前的值：2000，我得更小了

    private static boolean rateControl = true;
    private static long lastQueryTime = 0l;

    /**
     * Are we throttling queries to prevent being blocked? Defaults to 
true.
     * 
     * @return Returns true if throttling query frequency.
     */
    public static boolean isUsingRateControl() {
        return rateControl;
    }

    /**
     * Allows turning off rate control
     * 
     * @param rateControl Turns on rate control if true, off if false.
     */
    public static void setUsingRateControl(boolean rateControl) {
        Translate.rateControl = rateControl;
    }

    /**
     * Reads an InputStream and returns its contents as a String. Also 
effects rate control.
     * @param inputStream The InputStream to read from.
     * @return The contents of the InputStream as a String.
     * @throws Exception
     */
    private static String toString(InputStream inputStream) throws 
Exception {
        StringBuilder outputBuilder = new StringBuilder();
        try {
            while (rateControl && (lastQueryTime+RATE_DELAY > 
System.currentTimeMillis())) {
                try {
                    Thread.sleep(lastQueryTime+RATE_DELAY-
System.currentTimeMillis());
                } catch (InterruptedException e) {
                }
            }
            String string;
            if (inputStream != null) {
                BufferedReader reader = new BufferedReader(new 
InputStreamReader(inputStream, ENCODING));
                while (null != (string = reader.readLine())) {
                    outputBuilder.append(string).append('\n');
                }
            }
            if (rateControl) lastQueryTime = System.currentTimeMillis
();
        } catch (Exception ex) {
            throw new Exception("[google-api-translate-java] Error 
reading translation stream.", ex);
        }
        return outputBuilder.toString();
    }

    /**
     * Translates text from a given language to another given language 
using Google Translate
     * http://www.google.com/translate_t?hl=zh-CN
     * @param text The String to translate.
     * @param from The language code to translate from.
     * @param to The language code to translate to.
     * @return The translated String.
     * @throws MalformedURLException
     * @throws IOException
     */
    public static String translate(String text, String from, String to) 
throws Exception {
        if(Language.CHINESE.equals(from) && 
Language.CHINESE_TRADITIONAL.equals(to))
            from = Language.CHINESE_SIMPLIFIED;
        if (Language.isValidLanguagePair(from, to)) {
            return retrieveTranslation(text, from, to);
        } else {
            return retrieveTranslation(retrieveTranslation(text, from, 
INTERMEDIATE_LANGUAGE), INTERMEDIATE_LANGUAGE, to);
        }
    }

    /***
     * 设置代理
     * @param szProxyServer
     * @param szPort
     */
    public static void setProxy(String szProxyServer, String szPort)
    {
        System.getProperties().put("proxySet", "true");
        System.getProperties().put("proxyHost", szProxyServer);
        System.getProperties().put("proxyPort", szPort);
    }

    /**
     * Forms an HTTP request and parses the response for a translation.
     * 
     * @param text The String to translate.
     * @param from The language code to translate from.
     * @param to The language code to translate to.
     * @return The translated String.
     * @throws Exception
     */
    private static String retrieveTranslation(String text, String from, 
String to){//  throws Exception 
        try {
            if(null == text || 0 == text.length())return "";

            StringBuilder url = new StringBuilder();
            url.append(URL_STRING).append(from).append('|').append(to);

            HttpURLConnection uc = (HttpURLConnection) new URL
(url.toString()).openConnection();
            try {

                uc.setRequestProperty("User-Agent", "Mozilla/4.0 
(compatible; MSIE 7.0; Windows NT 5.1)");
                // 用post的方式能翻译大于1024字节的内容
                uc.setDoOutput(true);
                OutputStream out = uc.getOutputStream();
                out.write(("langpair=" + from + "|" + to + 
TEXT_VAR + URLEncoder.encode(text, ENCODING)).getBytes());
                out.flush();
                out.close();
                String page = toString(uc.getInputStream());

                int resultBox = page.indexOf("<div id=result_box 
dir=");        
                if (resultBox < 0) throw new Error("No translation 
result returned.");

                String start = page.substring(resultBox);
                return start.substring(start.indexOf('>')+1, 
start.indexOf("</div>"));
            } finally { // 
http://java.sun.com/j2se/1.5.0/docs/guide/net/http-keepalive.html
                try{
                    uc.getInputStream().close();
                }catch(Exception e){e.printStackTrace();}
                if (null != uc.getErrorStream()) uc.getErrorStream
().close();
                uc = null;
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
        return "";
    }
}

Original issue reported on code.google.com by miraclet...@gmail.com on 29 Jan 2008 at 6:06

[GoogleCodeExporter]

Hi, 
It seems the existing translation is using HTTP Get thus has a length limit for 
the
source string. However, since the source string, say Chinese, quite possibly is
encoded in UTF-8 when Google code is handling it and therefore difficult for us 
to
know the length before hand, making the translation less practical. So adopting 
a
POST based translation approach would really be IDEAL. 

Thanks.

QM

Original comment by qmwestv...@gmail.com on 27 May 2009 at 7:42

[GoogleCodeExporter]

[deleted comment]

[GoogleCodeExporter]

Hi, miracletalent,

Had a go with your code and it works great. Thank you so much.

A small question: Language.isValidLanguagePair(from, to) does not seem to be
supported by google-api-translate-java-0.53.jar. Are you using a newer version 
of it
in private or else?

Best regards,

Qunhuan

Original comment by qmwestv...@gmail.com on 29 May 2009 at 9:30

[GoogleCodeExporter]

[deleted comment]

[GoogleCodeExporter]

[deleted comment]

[GoogleCodeExporter]

Original comment by rich.mid...@gmail.com on 19 Sep 2009 at 6:06

• Changed state: WontFix