java-FileInputStream与FileOutputStream

package com.file;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

//代码胜千言
public class Demo5 {
	public static void main(String[] args) throws IOException, InterruptedException {
		//指定输入
		File inputFile = new File("E:"+File.separator+"z.jpg");
		//创建FileInputStream输入流对象。
		FileInputStream fileInputStream = new FileInputStream(inputFile);
		//指定输出
		File outPutFile = new File("F:"+File.separator+"a.jpg");
		//创建FileOutputStream输出流对象。
		FileOutputStream fileOutputStream= new FileOutputStream(outPutFile);
		//创建缓冲字符流--存储读取到的数据    缓冲数组 的长度一般是1024的倍数，因为与计算机的处理单位。  理论上缓冲数组越大，效率越高
		byte[] filebyte = new byte[1024];
		////保存每次读取到的字节个数。
		int length=0;
		//read()!=-1时,写入字节
		while((length=fileInputStream.read(filebyte))!=-1){
			//输出字节
			fileOutputStream.write(filebyte,0,length);
		}
		//关闭资源---先开后关，后开先关
		fileOutputStream.close();
		fileInputStream.close();
		
	}

}

异常处理

package com.file;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

public class Demo6 {
	public static void CopyImage(){
		File inputFile = new File("E:"+File.separator+"z.jpg");
		File outPutFile = new File("F:"+File.separator+"a.jpg");
		FileInputStream fileInputStream=null;
		FileOutputStream fileOutputStream=null;
		try{
			fileInputStream = new FileInputStream(inputFile);
			fileOutputStream= new FileOutputStream(outPutFile);
			byte[] filebyte = new byte[1024];
			int length=0;
			while((length=fileInputStream.read(filebyte))!=-1){
				fileOutputStream.write(filebyte,0,length);
			}
		}catch (Exception e) {
			System.out.println("拷贝图片失败.....");
			throw new RuntimeException(e);
		}finally{
				try {
					if(fileOutputStream!=null){
						fileOutputStream.close();
						System.out.println("关闭输出流成功....");
					}
					
				} catch (IOException e) {
					System.out.println("关闭输出流失败....");
					throw new RuntimeException(e);
				}
				try {
					if(fileInputStream!=null){
						fileInputStream.close();
						System.out.println("关闭输入流成功....");
					}
				} catch (IOException e) {
					System.out.println("关闭输入流失败....");
					throw new RuntimeException(e);
				}
		}
	}
	public static void main(String[] args) {
		CopyImage();
	}
}