下载.java
package com.example.download_file;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import android.os.Bundle;
import android.os.Environment;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
public class Download extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_download);
final Button downloadbutton=(Button)findViewById(R.id.download_button);
final EditText text=(EditText)findViewById(R.id.download_filename);
downloadbutton.setOnClickListener(new OnClickListener()
{
@Override
public void onClick(View v)
{
download();
text.setText("success");
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_download, menu);
download();
return true;
}
public void download()
{
final EditText text=(EditText)findViewById(R.id.download_filename);
final EditText localname=(EditText)findViewById(R.id.localname);
try {
String name=text.getText().toString();
String sdcardname=localname.getText().toString();
URL url = new URL(name);
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.connect();
File SDCardRoot = Environment.getExternalStorageDirectory();
File file = new File(SDCardRoot,sdcardname);
FileOutputStream fileOutput = new FileOutputStream(file);
InputStream inputStream = urlConnection.getInputStream();
int totalSize = urlConnection.getContentLength();
int downloadedSize = 0;
.
byte[] buffer = new byte[1024];
int bufferLength = 0;
while ( (bufferLength = inputStream.read(buffer)) > 0 ) {
fileOutput.write(buffer, 0, bufferLength);
}
fileOutput.close();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
1)
输入: url = "\192.168.0.103\shared\file.txt"
错误:java.net.MalformedURLException:找不到协议:\192.168.0.103\shared\file.txt
2)
输入:url =“文件://192.168.0.103/shared/file.txt”
错误:java.lang.ClassCastEXception:org.apache.harmony.luni.internal.net.www.protocol.ftp.FtpURLConnection