在做OCR时,我们会从服务器下载验证码图片,可以通过把验证码图片下载到本地保存起来使用。
以下是下载图片的实现:
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
public class Test {
public static final String URL_PATH = "http://member.0256.cn/Include/ASPX/CheckCode.aspx?rnd=0.7748341448605061"; // 实例图片,实际开发中可能是获得服务器上的所有图片,或者部分图片,不可能是具体某一张图片
// 把从服务器获得图片的输入流InputStream写到本地磁盘
public static void saveImageToDisk() {
InputStream inputStream = getInputStream();
byte[] data = new byte[1024];
int len = 0;
FileOutputStream fileOutputStream = null;
try {
fileOutputStream = new FileOutputStream("F:\\checkCode.jpg");
while ((len = inputStream.read(data)) != -1) {
fileOutputStream.write(data, 0, len);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (fileOutputStream != null) {
try {
fileOutputStream.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
// 从服务器获得一个输入流(本例是指从服务器获得一个image输入流)
public static InputStream getInputStream() {
InputStream inputStream = null;
HttpURLConnection httpURLConnection = null;
try {
URL url = new URL(URL_PATH);
httpURLConnection = (HttpURLConnection) url.openConnection();
// 设置网络连接超时时间
httpURLConnection.setConnectTimeout(3000);
// 设置应用程序要从网络连接读取数据
httpURLConnection.setDoInput(true);
httpURLConnection.setRequestMethod("GET");
int responseCode = httpURLConnection.getResponseCode();
if (responseCode == 200) {
// 从服务器返回一个输入流
inputStream = httpURLConnection.getInputStream();
System.out.println(inputStream + "**********************");
}
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return inputStream;
}
public static void main(String args[]) {
// 从服务器端获得图片,保存到本地
saveImageToDisk();
// File file = new File(
// "C://Program Files//Apache Software Foundation//Tomcat 6.0//webapps//plpwmanagers//DpImg//"); // 得到服务器上DpImg文件下所有图片
// String test[];
// test = file.list(); // 将每张图片依次存放到 test 数组中
//
// System.out.println(test.length);
// for (int i = 0; i < test.length; i++) {
// System.out.println(test[i]);
// }
}
}