Develop Reference

Can I import an image from any type of website?

I'm trying to import images from Internet using Java (IDE IntelliJ) but I don't know how to select an image (in this case the first of the row) from google images.
For example I tried to search the capital of Rome and Napoli, but the code can't find any image from images google's section.
Probably you don't understand much what I said, so below you will find the code I wrote with the relative error
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.URL;
public class Main{
public static void main(String[] args) {
String[] listaCapitali = {
"Roma",
"Napoli",
};
for (String capitale : listaCapitali) {
ricercaGoogle("https://www.google.com/search?q=" + capitale + "+cartina&source=lnms&tbm=isch&sa=X&ved=2ahUKEwj-moK1y-D0AhXIzaQKHeXUBLUQ_AUoAXoECAEQAw&cshid=1639392166213289&biw=2240&bih=1082&dpr=2");
}
}
private static void ricercaGoogle(String urlPath) {
try {
URL url = new URL(urlPath);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
int response = connection.getResponseCode();
System.out.println(response);
BufferedImage image = ImageIO.read(url);
FileOutputStream fos = new FileOutputStream(String.valueOf(image));
fos.write(response);
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
The error says:
403
javax.imageio.IIOException: Can't read input file!
at java.desktop/javax.imageio.ImageIO.read(ImageIO.java:1308)
at Main.ricercaGoogle(Main.java:33)
at Main.main(Main.java:19)
403
javax.imageio.IIOException: Can't read input file!
at java.desktop/javax.imageio.ImageIO.read(ImageIO.java:1308)
at Main.ricercaGoogle(Main.java:33)
at Main.main(Main.java:19)
Could you also help me to download those images on my computer named with the capital name? Thanks a lot

First thing to do :Your URL is not an URL of an Image ! try to change the URL
You can inspire from that code it works fine :
Get an image from a HTTPGET and Put it on a file
new Thread(new Runnable() {
#Override
public void run() {
HttpClient httpclient = HttpClients.createDefault();
/*
* put your urlPath here instead of http://localhost...
*/
HttpGet httpget = new HttpGet("http://localhost:9090/imageFilm/1");
// Execute and get the response.
HttpResponse response = null;
try {
response = httpclient.execute(httpget);
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
HttpEntity entity = response.getEntity();
if (entity != null) {
try (InputStream instream = entity.getContent()) {
// receiving an image and write it within a file
try (FileOutputStream outputStream = new FileOutputStream(
/*
* here i create a file with the image received from the httpGet , you can do other things
*/
new File("C:\\Users\\OUSSAMA\\Desktop\\xc.png"), false)) {
int read;
byte[] bytes = new byte[1024];
while ((read = instream.read(bytes)) != -1) {
outputStream.write(bytes, 0, read);
}
}
} catch (UnsupportedOperationException | IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}).start();
Apache HttpClient dependency needed :
https://mvnrepository.com/artifact/org.apache.httpcomponents/httpclient/4.5.13
All The code in one class :
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.HttpClients;
public class Main{
public static void main(String[] args) {
String[] listaCapitali = {
"Roma",
"Napoli",
};
for (String capitale : listaCapitali) {
//ricercaGoogle("https://www.google.com/search?q=" + capitale + "+cartina&source=lnms&tbm=isch&sa=X&ved=2ahUKEwj-moK1y-D0AhXIzaQKHeXUBLUQ_AUoAXoECAEQAw&cshid=1639392166213289&biw=2240&bih=1082&dpr=2");//Your URL is not an URL of an Image ; you must change it !
ricercaGoogle("https://i.pinimg.com/originals/1b/75/84/1b758419a811ae05ad4da61acdb7ce22.jpg");
}
}
private static void ricercaGoogle(String urlPath) {
HttpClient httpclient = HttpClients.createDefault();
/*
* put your urlPath here instead of http://localhost...
*/
HttpGet httpget = new HttpGet(urlPath);
// Execute and get the response.
HttpResponse response = null;
try {
response = httpclient.execute(httpget);
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
HttpEntity entity = response.getEntity();
if (entity != null) {
try (InputStream instream = entity.getContent()) {
// receiving an image and write it within a file
try (FileOutputStream outputStream = new FileOutputStream(
/*
* here i create a file with the image received from the httpGet , you can do other things
*/
new File("C:\\Users\\Mourad\\Desktop\\xc.png"), false)) {
int read;
byte[] bytes = new byte[1024];
while ((read = instream.read(bytes)) != -1) {
outputStream.write(bytes, 0, read);
}
}
} catch (UnsupportedOperationException | IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}

I am trying to show the download speed(seconds ) and the size in KB for an URL in Java

I need to read the URL addresses from a file and show the download speed , title tag , and the size in KB.
I am stuck with the size , getContentLengthLong() is negative ,
I am not sure if it`s correct but I tried :
connection.setRequestProperty("Accept-Encoding", "identity");
and I need some help with the download speed .
import java.net.URL;
import java.net.URLConnection;
import java.util.Scanner;
import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
public class UrlReader {
static void readTextFromURL( String urlString ) throws IOException {
System.out.print(urlString + "\t"); // print the url
URL url = new URL(urlString);
URLConnection connection = url.openConnection();
connection.setRequestProperty("Accept-Encoding", "identity");
InputStream urlData = connection.getInputStream();
//print the title
Scanner scanner = new Scanner(urlData);
String responseBody = scanner.useDelimiter("\\A").next();
System.out.print(responseBody.substring(responseBody.indexOf("<title>") + 7, responseBody.indexOf("</title>")) + "\t");
//print the size in KB
long file_size = connection.getContentLengthLong();
if (file_size < Long.MAX_VALUE){
System.out.println(file_size/1024 + "KB");
}
// print the download speed(seconds)
urlData.close();
scanner.close();
} // end readTextFromURL()
public static void main(String[] args) {
try{
File file = new File("data.txt");
FileInputStream ft = new FileInputStream(file);
DataInputStream in = new DataInputStream(ft);
BufferedReader br = new BufferedReader(new InputStreamReader(in));
String strline;
String url; // The url from the command line or from user input.
String urlLC;
while((strline = br.readLine()) != null){
url = strline;
urlLC = url.toLowerCase();
if ( ! (urlLC.startsWith("http://") || urlLC.startsWith("ftp://") ||urlLC.startsWith("https://")||
urlLC.startsWith("file://"))) {
url = "http://" + url;
}
try {
readTextFromURL(url);
}
catch (IOException e) {
System.out.println("\n*** Sorry, an error has occurred ***\n");
System.out.println(e);
}
}
in.close();
}catch(Exception e){
System.err.println("Error: " + e.getMessage());
}
} // end main
}

Example of POST request in Android studio

I just started learning android few days ago and I have a problem with uploading my JSON data to server. I manage to retrieve it via following code:
Edit: I did manage to retrieve files using external OKHTTP library but I would like to do this without using external libraries.
package cc.demorest;
import android.os.AsyncTask;
import android.renderscript.ScriptGroup;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.widget.EditText;
import android.widget.TextView;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
setContentView(R.layout.activity_main);
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
DownloadTask task = new DownloadTask();
task.execute("myserver.com");
}
//Downloadtask
public class DownloadTask extends AsyncTask<String,Void,String> {
#Override
protected String doInBackground(String... urls) {
String result = "";
URL url;
HttpURLConnection urlConnection=null;
try {
url = new URL(urls[0]);
urlConnection=(HttpURLConnection)url.openConnection();
InputStream in = urlConnection.getInputStream();
InputStreamReader reader = new InputStreamReader(in);
int data=reader.read();
while (data !=-1){
char current=(char) data;
result += current;
data = reader.read();
}
return result;
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
//After download task
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
try {
JSONArray jArray=new JSONArray(result);
JSONObject json_data = jArray.getJSONObject(1);
//Logging data
Log.i("Podatci: ", "Id: " + json_data.getInt("Id") +
", Name: " + json_data.getString("Name") +
", Years: " + json_data.getString("Age") +
", Email address: " + json_data.getString("Email")
);
TextView textView = (TextView) findViewById(R.id.textViewName);
textView.setText("ID: "+", Name: "+ json_data.getInt("Id")+json_data.getString("Name")+json_data.getString("Age")+json_data.getString("Email"));
/*
String data = jsonObject.getString("Name");
Log.i("Website content", data);
*/
} catch (JSONException e) {
e.printStackTrace();
}
}
}
}
I am now trying to send my data to same server with same fields. I searched internet but most things that I found are outdated.. I would really appriciate some help or example.
Best Regards

Use HttpURLConnection, it does not use external libraries. If you're going to use an HttpURLConnection, it needs to be an AsyncTask.
Here is my code from a project I completed. Hope it helps.
First, put this in your manifest.xml file before :
<uses-permission android:name="android.permission.INTERNET" />
Calling the AsyncTask:
(Ignore the this, SinceTime, and GoesAddress. They are just variables I passed in)
URL url = new URL("https://eddn.usgs.gov/cgi-bin/fieldtest.pl");
new ReceiveData(this, SinceTime, GoesAddress).execute(url);
The Class:
package com.ryan.scrapermain;
import android.content.Context;
import android.os.AsyncTask;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLEncoder;
import java.util.HashMap;
import java.util.Map;
import javax.net.ssl.HttpsURLConnection;
public class ReceiveData extends AsyncTask<URL, Integer, Long> {
String response = "";
String SinceTime;
String GoesAddress;
Context myContext;
ReceiveData(Context context, String since, String goes) {
this.myContext = context;
SinceTime = since;
GoesAddress = goes;
}
private String getPostDataString(HashMap<String, String> params) throws UnsupportedEncodingException {
StringBuilder feedback = new StringBuilder();
boolean first = true;
for(Map.Entry<String, String> entry : params.entrySet()){
if (first)
first = false;
else
feedback.append("&");
feedback.append(URLEncoder.encode(entry.getKey(), "UTF-8"));
feedback.append("=");
feedback.append(URLEncoder.encode(entry.getValue(), "UTF-8"));
}
return feedback.toString();
}
public void getData() throws IOException {
HashMap<String, String> params = new HashMap<>();
params.put("DCPID", GoesAddress);
params.put("SINCE", SinceTime);
URL url = new URL("https://eddn.usgs.gov/cgi-bin/fieldtest.pl");
HttpURLConnection client = null;
try {
client = (HttpURLConnection) url.openConnection();
client.setRequestMethod("POST");
// You need to specify the context-type. In this case it is a
// form submission, so use "multipart/form-data"
client.setRequestProperty("multipart/form-data", "https://eddn.usgs.gov/fieldtest.html;charset=UTF-8");
client.setDoInput(true);
client.setDoOutput(true);
OutputStream os = client.getOutputStream();
BufferedWriter writer = new BufferedWriter(
new OutputStreamWriter(os, "UTF-8"));
writer.write(getPostDataString(params));
writer.flush();
writer.close();
os.close();
int responseCode = client.getResponseCode();
if (responseCode == HttpsURLConnection.HTTP_OK) {
String line;
BufferedReader br = new BufferedReader(new InputStreamReader(client.getInputStream()));
while ((line = br.readLine()) != null) {
response += line;
}
}
else {
response = "";
}
}
catch (MalformedURLException e){
e.printStackTrace();
}
finally {
if(client != null) // Make sure the connection is not null.
client.disconnect();
}
}
#Override
protected Long doInBackground(URL... params) {
try {
getData();
} catch (IOException e) {
e.printStackTrace();
}
// This counts how many bytes were downloaded
final byte[] result = response.getBytes();
Long numOfBytes = Long.valueOf(result.length);
return numOfBytes;
}
protected void onPostExecute(Long result) {
System.out.println("Downloaded " + result + " bytes");
// This is just printing it to the console for now.
System.out.println(response);
// In the following two line I pass the string elsewhere and decode it.
InputCode input = new InputCode();
input.passToDisplay(myContext, response);
}
}

Use Volley as defined here. It's far more easier.

wait for php script then download

i have a php script which creates a file if it not exists. the php script sends the file after it created it. now i have the problem that my download class can't download it (i don't know exactly why) when the php file is creating a new file. but if the php script sends a cached file the download works.
Is there any way to let the android wait until the php script is done executing?
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;
import java.net.URLConnection;
import org.json.JSONObject;
import android.os.AsyncTask;
import android.os.Environment;
import android.os.Looper;
import android.provider.ContactsContract.Directory;
import android.util.Log;
public class DownloadMP3 extends AsyncTask<String, Integer, String> {
private OnTaskRunning listener;
public DownloadMP3(OnTaskRunning listener){
this.listener=listener;
}
#Override
protected String doInBackground(String... url) {
int count;
try {
Log.d("Info", "create file");
Download down = new Download();
JSONObject jObject = new JSONObject(down.JSON(conf.d + "convert.php?v=" + url[0]));
Log.d("Info","json file: " + jObject.get("fle"));
URL u = new URL(conf.d + "convert.php?v=" + jObject.get("fle"));
Log.d("Info", "dl u");
URLConnection conexion = u.openConnection();
Log.d("Info", "dl op");
conexion.connect();
Log.d("Info", "dl co");
File directory = new File(Environment.getExternalStorageDirectory() + "/Music/VBT Splash/");
Log.d("Info", "dl di");
if (!directory.exists() || !directory.isDirectory()){
directory.mkdirs();
}
InputStream input = new BufferedInputStream(u.openStream());
String filename = conexion.getHeaderField("Content-Disposition");
String file = filename.substring(filename.indexOf("\"")+1, filename.lastIndexOf("\""));
OutputStream output = new FileOutputStream(Environment.getExternalStorageDirectory() + "/Music/VBT Splash/" + file);
int lenghtOfFile = conexion.getContentLength();
byte data[] = new byte[4096];
long total = 0;
listener.onTaskStarted();
while ((count = input.read(data)) != -1) {
total += count;
output.write(data, 0, count);
publishProgress((int) (total * 100 / lenghtOfFile));
}
Log.d("Info", "dl done");
listener.onTaskDone();
output.flush();
output.close();
input.close();
} catch (Exception e) {
}
return null;
}
protected void onProgressUpdate(Integer... progress) {
listener.onTaskProgress(progress[0]);
}
protected void onPostExecute(int result) {
}
}

You must convey a re-direct to your client code. If you just hit the full file path url , and it doesn't exists, it won't be downloaded. So instead, first get download url from script. ( a new one will be created if it doesn't exists) then, download that url. That makes a total of 2 requests to server.

Android Json HTTP Post, Unable to parse data

Sorry to trouble you, as I am new to Android programming, and i have face the following problem while trying retrieve my send and receive a response from my local host server.
The program seem to auto close when i try to launch it at first. But after implementing
StrictMode.ThreadPolicy policy = new StrictMode.
ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
The program is able to run, however, the data is not parse across.
I have allowed the Internet permission in my android Manifest script.
My Android Codes
package kx.practice;
import android.app.Activity;
import android.os.Bundle;
import android.os.StrictMode;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.widget.TextView;
public class JsonHttpPractice2Activity extends Activity {
TextView tv;
String text;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
StrictMode.ThreadPolicy policy = new StrictMode.
ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
tv = (TextView)findViewById(R.id.textView1);
text = "";
try {
postData();
} catch (JSONException e) {
// TODO Auto-generated catch block
System.out.println("Error in JSON Exception 1");
e.printStackTrace();
}
}
public void postData() throws JSONException{
// Create a new HttpClient and Post Header
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://localhost/phpWebservice/AndroidTest.php");
JSONObject json = new JSONObject();
try {
// JSON data:
json.put("name", "Fahmi Rahman");
json.put("position", "sysdev");
JSONArray postjson=new JSONArray();
postjson.put(json);
// Post the data:
httppost.setHeader("json",json.toString());
httppost.getParams().setParameter("jsonpost",postjson);
// Execute HTTP Post Request
System.out.print(json);
HttpResponse response = httpclient.execute(httppost);
// for JSON:
if(response != null)
{
InputStream is = response.getEntity().getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
StringBuilder sb = new StringBuilder();
String line = null;
try {
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
text = sb.toString();
System.out.println("This is my text" +text);
}
tv.setText(text);
}catch (ClientProtocolException e) {
System.out.println("Error in JSON Exception 2");
// TODO Auto-generated catch block
} catch (IOException e) {
System.out.println("Error in JSON Exception 3");
// TODO Auto-generated catch block
}
}
}
And lastly, my PHP codes
<?php
$json = $_SERVER['HTTP_JSON'];
echo "JSON: \n";
echo "--------------\n";
var_dump($json);
echo "\n\n";
$data = json_decode($json);
echo "Array: \n";
echo "--------------\n";
var_dump($data);
echo "\n\n";
$name = $data->name;
$pos = $data->position;
echo "Result: \n";
echo "--------------\n";
echo "Name : ".$name."\n Position : ".$pos;
?>
By the way, I got these codes from an online website. However, if these codes are able to work, i should be able to implement it into my project.

You are trying to access the network on the main thread. This is a very bad idea. You need to do the network access in a separate thread instead. The linked article provides several guidelines for doing this.
If you still have problems after moving the network access to a different thread, then feel free to come back and ask more questions.
(The reason your app was killed is because the Android system noticed it hadn't responded for a while, since it was waiting for network traffic.)