java获取本地文件和远程文件的方式代码示例

import java.net.HttpURLConnection;
import java.io.*;
import java.net.URL;
import java.net.URLConnection;
public byte[] getFile(String filePath) {
        int HttpResult; // 服务器返回的状态
        byte[] bytes = new byte[204800]; //设置数组大小
        try
        {
            URL url =new URL(filePath); // 创建URL
            URLConnection urlconn = url.openConnection(); // 试图连接并取得返回状态码
            urlconn.connect();
            HttpURLConnection httpconn =(HttpURLConnection)urlconn;
            HttpResult = httpconn.getResponseCode();
            if(HttpResult != HttpURLConnection.HTTP_OK) {
            	log.error("获取文件失败，无法连接到文件资源")
            } else {
                int filesize = urlconn.getContentLength(); // 取数据长度
                log.info("取数据长度:{}",filesize)
                urlconn.getInputStream();
                InputStream inputStream = urlconn.getInputStream();
				//如果这里只需要返回stream，则直接返回 不需要转byte[]
                ByteArrayOutputStream swapStream = new ByteArrayOutputStream();
                int ch;
                while ((ch = inputStream.read()) != -1) {
                    swapStream.write(ch);
                }
                bytes = swapStream.toByteArray();
            }
            log.info("文件大小，length:{}",bytes.length);
        }
        catch (Exception e) {
        	log.error("获取文件异常，e:{}",e);
        }
        return  bytes;
    }

File file = new File("/resource/static/sdsadc12.jpg");
		InputStream in = null;
		try {
			// 一次读多个字节
			byte[] tempbytes = new byte[100];
			int byteread = 0;
			in = new FileInputStream(file);
			// 读入多个字节到字节数组中，byteread为一次读入的字节数
			while ((byteread = in.read(tempbytes)) != -1) {
				System.out.write(tempbytes, 0, byteread);
			}
			log.info("文件大小:{}"+file.length());
		} catch (Exception ee) {
			log.error("异常:{}",ee);
		} finally {
			if (in != null) {
				try {
					in.close();
				} catch (IOException e1) {
				}
			}
		}