java-FileInputStream與FileOutputStream

package com.file;

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

//代碼勝千言
public class Demo5 {
	public static void main(String[] args) throws IOException, InterruptedException {
		//指定輸入
		File inputFile = new File("E:"+File.separator+"z.jpg");
		//創建FileInputStream輸入流對象。
		FileInputStream fileInputStream = new FileInputStream(inputFile);
		//指定輸出
		File outPutFile = new File("F:"+File.separator+"a.jpg");
		//創建FileOutputStream輸出流對象。
		FileOutputStream fileOutputStream= new FileOutputStream(outPutFile);
		//創建緩衝字符流--存儲讀取到的數據    緩衝數組 的長度一般是1024的倍數，因爲與計算機的處理單位。  理論上緩衝數組越大，效率越高
		byte[] filebyte = new byte[1024];
		////保存每次讀取到的字節個數。
		int length=0;
		//read()!=-1時,寫入字節
		while((length=fileInputStream.read(filebyte))!=-1){
			//輸出字節
			fileOutputStream.write(filebyte,0,length);
		}
		//關閉資源---先開後關，後開先關
		fileOutputStream.close();
		fileInputStream.close();
		
	}

}

異常處理

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("拷貝圖片失敗.....");
			throw new RuntimeException(e);
		}finally{
				try {
					if(fileOutputStream!=null){
						fileOutputStream.close();
						System.out.println("關閉輸出流成功....");
					}
					
				} catch (IOException e) {
					System.out.println("關閉輸出流失敗....");
					throw new RuntimeException(e);
				}
				try {
					if(fileInputStream!=null){
						fileInputStream.close();
						System.out.println("關閉輸入流成功....");
					}
				} catch (IOException e) {
					System.out.println("關閉輸入流失敗....");
					throw new RuntimeException(e);
				}
		}
	}
	public static void main(String[] args) {
		CopyImage();
	}
}