mainActivity

package com.capital.connectmysql;

import android.content.Intent;
import android.net.Uri;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

    private UploadTask task;
    private TextView textView;
    private EditText editText;

    String url = "http://hpscript/android/pass_check.html";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        editText = findViewById(R.id.uriname);

        Button post = findViewById(R.id.post);

        post.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View v){
                String param0 = editText.getText().toString();

                if(param0.length() != 0){
                    task = new UploadTask();
                    task.setListener(createListener());
                    task.execute(param0);
                }
            }
        });

        Button browser = findViewById(R.id.browser);
        browser.setOnClickListener(new View.OnClickListenr(){
            @Override
            public void onClick(View v){
                Uri uri = Uri.parse(url);
                Intent intent = new Intent(Intent.ACTION_VIEW,uri);
                startActivity(intent);

                textView.setText("");
            }
        });
        textView = findViewById(R.id.text_view);
    }

    @Override
    protected void onDestroy(){
        task.setListener(null);
        super.onDestory();
    }

    private UploadTask.Listener createListener(){
        return new UploadTask.Listener(){
            @Override
            public void onSuccess(String result){
                textView.setText(result);
            }
        };
    }
}

package com.capital.connectmysql;

import android.net.sip.SipAudioCall;
import android.os.AsyncTask;
import android.util.Log;

import java.io.IOException;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;

public class UploadTask extends AsyncTask<String, Void, String> {

    private SipAudioCall.Listener listener;

    @Override
    protected String doInBackground(String... params){

        String urlSt = "http://hpscript.com/";

        HttpURLConnection con = null;
        String result = null;
        String word = "word="+params[0];

        try {
            URL url = new URL(urlSt);

            con = (HttpURLConnection) url.openConnection();

            con.setRequestMethod("POST");
            con.setInstanceFollowRedirects(false);
            con.setDoOutput(true);

            con.setReadTimeout(10000);
            con.setConnectTimeout(20000);

            con.connect();

            OutputStream out = null;
            try {
                out = con.getOutputStream();
                out.write( word.getBytes("UTF-8"));
                out.flush();
                Log.d("dubug", "flush");
            } catch (IOException e){
                e.printStackTrack();
                result = "POST送信エラー";
            } finally {
                if (out != null){
                    out.close();
                }
            }
            final int status = con.getResponseCode();
            if (status == HttpURLConnection.HTTP_OK){
                result = "HTTP_OK";
            } else {
                result = "status="+String.valueOf(status);
            }
        } catch(IOException e){
            e.printStackTrace();
        } finally {
            if (con != null){
                con.disconnect();
            }
        }
        return result;
    }

    @Override
    protected void onPostExecute(String result){
        super.onPostExecute(result);

        if(listener != null){
            listener.onSuccess(result);
        }
    }

    void setListener(SipAudioCall.Listener listener){
        this.listener = listener;
    }

    interface Listener {
        void onSuccess(String result);
    }
}