RandomAccessFile vs FileChannel.open(path);
What kind of FileChannel
object does the FileChannel.open(path)
method return?
Is it still random access allowed as if it was as following?
RandomAccessFile ra = new RandomAccessFile("RandomIndeed","rw");
FileChannel fc1 = ra.getChannel();
What's the difference between fc1
and the following instance fc
:
FileChannel fc = FileChannel.open(path);
Basically I would like to know what will be the differences between the 2 objects above-created, hence fc1
and fc
Thanks in advance.
The FileChannel
instance got from RandomAccessFile
instance carries the random access behaviour of the object it's been created, in this case fc1
is synced with ra
object. You can see it's described in javadoc
Changing the channel's position, whether explicitly or by reading or writing bytes, will change the file position of the originating object, and vice versa. Changing the file's length via the file channel will change the length seen via the originating object, and vice versa. Changing the file's content by writing bytes will change the content seen by the originating object, and vice versa.
However the FileChannel
instance which is created using FileChannel.open()
which is fc
doesn't have this behaviour. This is true for the FileChannel
instances you got from Streams. It only guarantees that the view of the file is consistent among the objects created by the same program. Hope this might help you.
RandomAccessFile vs FileChannel.open(path);的更多相关文章
- RandomAccessFile、FileChannel、MappedByteBuffer读写文件
s package com.nio; import java.io.Closeable; import java.io.FileNotFoundException; import java.io.IO ...
- FileChannel详解
经过前两篇文章的学习,相信对Channel有了一定的整体性认识.接下来通过学习本篇文章,更进一步认识Channel,学习FileChannel的细节 用途 特点 api 原理 一.用途 传统IO中的F ...
- Java NIO 文件通道 FileChannel 用法
FileChannel 提供了一种通过通道来访问文件的方式,它可以通过带参数 position(int) 方法定位到文件的任意位置开始进行操作,还能够将文件映射到直接内存,提高大文件的访问效率.本文将 ...
- java的nio之:java的nio系列教程之FileChannel
一:Java NIO的FileChannel===>Java NIO中的FileChannel是一个连接到文件的通道.可以通过文件通道读写文件. ===>FileChannel无法设置为非 ...
- Java基础知识强化之IO流笔记78:NIO之 FileChannel
Java NIO中的FileChannel是一个连接到文件的通道.可以通过文件通道读写文件. FileChannel无法设置为非阻塞模式,它总是运行在阻塞模式下. 1. 打开FileChannel 在 ...
- 【原创】java NIO FileChannel 学习笔记 新建一个FileChannel
首先使用FileChannel 的open方法获取一个FileChannel对象.下面这段代码是FileChannel中open方法的代码. public static FileChannel ope ...
- Java NIO系列教程(二) Channel通道介绍及FileChannel详解
目录: <Java NIO系列教程(二) Channel> <Java NIO系列教程(三) Channel之Socket通道> Channel是一个通道,可以通过它读取和写入 ...
- Java NIO系列教程(七) FileChannel
Java NIO中的FileChannel是一个连接到文件的通道.可以通过文件通道读写文件. FileChannel无法设置为非阻塞模式,它总是运行在阻塞模式下. 打开FileChannel 在使用F ...
- FileChannel指南
推荐关注公众号:锅外的大佬 每日推送国外技术好文,帮助每位开发者更优秀地成长 原文链接:https://www.baeldung.com/java-filechannel 作者:baeldung 译者 ...
随机推荐
- Bacula Plugins
1. loadPlugin 插件通过加载动态库loadPlugin函数开始,此函数包括bacula的回调和Plugin的注册 bacula的回调 typedef struct s_baculaFunc ...
- Hive:数据倾斜
数据倾斜问题 数据倾斜是大数据领域绕不开的拦路虎,当你所需处理的数据量到达了上亿甚至是千亿条的时候,数据倾斜将是横在你面前一道巨大的坎.很可能有几周甚至几月都要头疼于数据倾斜导致的各类诡异的问题. 数 ...
- 关于重学Linux的随笔
毕业已有半年, 现在想想真的后悔, 大学没有认真学Linux, 导致现在Linux操作抓瞎, 连服务器都搭不起来. 下定决心重学Linux, 不追求能比上大佬, 但是要熟练, 常用命令要熟悉. 作为一 ...
- Debian x7中如何添加永久环境变量
一.进入/etc/bash.bashrc(使用文本编辑器打开) 二.在最后面添加新的环境变量 export PATH=usr/...(路径):$PATH 三.保存后,打开终端,输入source ~/. ...
- python+openpyxl的excel的相关读写
def test(): wb2 = openpyxl.Workbook() #创建一个excel对象 wb2.save("a.xlsx") #保存excel并命名为a.xlsx w ...
- dp的一些练习
#include<iostream> #include<vector> using namespace std; class Backpack { public: int ma ...
- com.github.pagehelper.PageHelper cannot be cast to org.apache.ibatis.plugin.Interceptor
在MyBatis的配置文件中修改对pageHelper的配置修改前 <plugins> <plugin interceptor="com.github.pagehelper ...
- IDEA中的模板文件设置
idea中的设置 Settings>Editor>File and code Templates>Includes>File Header 中粘贴下面的表达格式 /** * @ ...
- Linux学习笔记-第7天 - 编程还是要多写多练
编程思路很重要,多写是要熟悉命令用法,多练不只是要熟悉语句常用在什么环境,更要在其基础上,尝试更多的写法.
- [LeetCode] 153. Find Minimum in Rotated Sorted Array 寻找旋转有序数组的最小值
Suppose an array sorted in ascending order is rotated at some pivot unknown to you beforehand. (i.e. ...