根据url下载文件java后端 java根据文件路径下载文件

import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;

public class TestUtil {
    /*
    根据文件所在路径下载文件
     */
    public void download(HttpServletResponse response, String filePath){
        File file = new File(filePath);
        // 取得文件名。
        String fileName = file.getName();
        InputStream fis = null;
        try {
            fis = new FileInputStream(file);
            response.reset();
            response.setCharacterEncoding("UTF-8");
            response.setContentType("application/force-download");// 设置强制下载不打开
            response.addHeader("Content-Disposition",
                    "attachment;filename=" + new String(fileName.getBytes("utf-8"), "iso8859-1"));
            response.setHeader("Content-Length", String.valueOf(file.length()));

            byte[] b = new byte[1024];
            int len;
            while ((len = fis.read(b)) != -1) {
                response.getOutputStream().write(b, 0, len);
            }
            response.flushBuffer();
            fis.close();
        }catch (IOException e) {
            throw new RuntimeException(e);
        }
    }
}

　　如以上方法在不同浏览器下载文件名乱码，可换用以下方法：

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URLEncoder;

public class TestUtil {
    /*
    根据文件所在路径下载文件
     */
    public void download(HttpServletRequest request, HttpServletResponse response, String filePath){
        File file = new File(filePath);
        // 取得文件名。
        String fileName = file.getName();
        InputStream fis = null;
        try {
            fis = new FileInputStream(file);
            request.setCharacterEncoding("UTF-8");
            String agent = request.getHeader("User-Agent").toUpperCase();
            if ((agent.indexOf("MSIE") > 0) || ((agent.indexOf("RV") != -1) && (agent.indexOf("FIREFOX") == -1)))
                fileName = URLEncoder.encode(fileName, "UTF-8");
            else {
                fileName = new String(fileName.getBytes("UTF-8"), "ISO8859-1");
            }
            response.reset();
            response.setCharacterEncoding("UTF-8");
            response.setContentType("application/force-download");// 设置强制下载不打开
            response.addHeader("Content-Disposition", "attachment;filename=" + fileName);
            response.setHeader("Content-Length", String.valueOf(file.length()));

            byte[] b = new byte[1024];
            int len;
            while ((len = fis.read(b)) != -1) {
                response.getOutputStream().write(b, 0, len);
            }
            response.flushBuffer();
            fis.close();
        }catch (IOException e) {
            throw new RuntimeException(e);
        }
    }
}