Sync

One-Way Directory or File Synchronization Tool. Free software written in Java.
Latest version: 2.1 (2007-12-09)

Simple command-line utility for one-way directory or file synchronization. Synchronize a specified target directory or file to match a specified source directory or file. Only the target is modified. Flexible file-matching: combinations of name, size, time, CRC. Flexible file time comparison: specify time-tolerance in milliseconds. Filename filters: specify multiple GLOB or REGEX filters. Simulation mode: useful for just comparing directories or files. Ideal for scripted or unattended usage. Free software written in Java.

Brief Description

Sync is a simple command-line utility for performing one-way directory or file synchronization. It synchronizes the specified target to match the specified source. Only the target is modified. Runs on any OS with the Java Runtime Environment (JRE 6+). Sync is free software written in Java and released under the GNU GPL license (version 3).

Main Features

Flexible File-Matching: Match files by combinations of name, size, last-modified time, and CRC-32 checksum; by default, (name,size,time,crc) are used.
Flexible File Time Comparison: Specify a time-tolerance (in milliseconds) when matching files by their last-modified time.
Filename Filters: Use multiple GLOB or REGEX filters to include or exclude files based on their names or their relative pathnames.
Simulation Mode: Sync can be run to simulate file operations, so that the target directory is not modified.
Unattended Usage: With an appropriate choice of switches, Sync can be executed without user intervention.
Log File: Sync can generate log files with automatic timestamps for convenient record-keeping.

Screenshots

Example of directory synchronization.

System Requirements

A Java Runtime Environment (JRE 6+) is required. The latest version of the JRE can be downloaded from http://java.sun.com/j2se.

License

Sync is released with source code under the GNU General Public License (version 3).

Installation & Execution

The Sync utility is downloaded as a single Zip file with the following contents:

Sync.jar – Sync executable JAR archive
readme.txt – Release notes
license.txt – License document (GNU GPLv3)
unix/Sync – Unix/Linux script for executing Sync
windows/Sync.bat – Windows batch file for executing Sync
src/ – Source files

No installation is necessary — just unzip the downloaded file and you are ready to go. Assuming that the executable JAR archive Sync.jar is in the current directory, simply execute the following at the command-line:

java -jar Sync.jar

Several pages of documentation (usage syntax, notes, and examples) should fill the screen. The use of the Windows batch file (windows/Sync.bat) or the Unix/Linux script (unix/Sync) is recommended because it enables you to simply execute Sync instead of java -jar Sync.jar. Further instructions are given in the respective files.

Source Code

src/sync/Sync.java
src/sync/SyncIO.java
src/sync/FileUnit.java
src/sync/FileUnitComparator.java
src/sync/FilterNode.java
src/sync/FilePair.java
src/sync/TerminatingException.java

Documentation

Usage Syntax

java -jar Sync.jar <switches> ["Source"] ["Target"]

Synchronize ["Target"] to match ["Source"]. Only ["Target"] is modified. By default, the filename, size, last-modified time, and CRC-32 checksum are used for file-matching. The synchronization mode depends on ["Source"]:

["Source"] is a DIRECTORY: Match source and target directories recursively. Matched target files are time-synced and renamed if necessary, unmatched source files are copied to the target directory, and unmatched target files/directories are deleted.
["Source"] is a FILE: Match source and target files, ignoring filename. If files match, then the target file is time-synced and renamed if necessary. If target file does not exist, then the source file is copied to the target.

`<Switches>`

`−s`, `−−simulate`	Simulate only; do not modify target
`−−ignorewarnings`	Ignore warnings; do not pause
`−l`, `−−log:<x>`	Create log file `x`; if `x` is not specified, "sync.yyyyMMdd-HHmmss.log" is used
`−r`, `−−norecurse`	Do not recurse into subdirectories
`−n`, `−−noname`	Do not use filename for file-matching
`−t`, `−−notime`	Do not use last-modified time for file-matching
`−c`, `−−nocrc`	Do not use CRC-32 checksum for file-matching
`−−time:[x]`	Use a `x`-millisecond time-tolerance for file-matching (0-millisecond time-tolerance is used by default; use `−−time:1000` or more to avoid mismatches across different file systems)
`−−rename:[y\|n]`	Always[`y`]/never[`n`] rename matched target files
`−−synctime:[y\|n]`	Always[`y`]/never[`n`] synchronize time of matched target files
`−−overwrite:[y\|n]`	Always[`y`]/never[`n`] overwrite existing target files/directories
`−−delete:[y\|n]`	Always[`y`]/never[`n`] delete unmatched target files/directories
`−−force`	Equivalent to the combination: `−−rename:y −−synctime:y −−overwrite:y −−delete:y`

A subset of source and/or target files/directories can be selected for synchronization using GLOB (or REGEX) filename filters. A file/directory is selected if it matches any of the "include" filters and none of the "exclude" filters.

`−i`, `−−include:["x"]`	Include source and target files/directories with names matching GLOB expression `x`
`−x`, `−−exclude:["x"]`	Exclude source and target files/directories with names matching GLOB expression `x`
`−is`, `−−includesource:["x"]`	Include source files/directories with names matching GLOB expression `x`
`−xs`, `−−excludesource:["x"]`	Exclude source files/directories with names matching GLOB expression `x`
`−it`, `−−includetarget:["x"]`	Include target files/directories with names matching GLOB expression `x`
`−xt`, `−−excludetarget:["x"]`	Exclude target files/directories with names matching GLOB expression `x`
`−p`, `−−path`	Filter relative pathnames instead of filenames (e.g. "work\report\jan.txt" instead of "jan.txt")
`−w`, `−−lower`	Use lower case names for filtering (e.g. "HelloWorld2007.JPG" → "helloworld2007.jpg")
`−−regex`	Use REGEX instead of GLOB filename filters (see Java API for REGEX syntax)

GLOB syntax:

`*`	Match a string of 0 or more characters
`?`	Match exactly 1 character
`[ ]`	Match exactly 1 character inside the brackets: `[abc]` match a, b, or c `[!abc]` match any character except a, b, or c (negation) `[a-z0-9]` match any character a through z, or 0 through 9, inclusive (range)
`{ }`	Match exactly 1 comma-delimited string from inside the braces: `{a,bc,def}` match either a, bc, or def

To use a construct symbol (e.g. [, {, ?) as a literal character, insert a backslash before it, e.g. use \[ for the literal character [. Use \\ for the literal backslash character \.

The file separator in Windows can be specified by \\ or /.

Examples

Synchronize target "C:\Backup" to look like source "C:\Original", matching files by (name,size,time,crc):
java -jar Sync.jar "C:\Original" "C:\Backup"
As in example 1, but never delete unmatched target files/directories:
java -jar Sync.jar −−delete:n "C:\Original" "C:\Backup"
As in example 1, but match files by (name,size,time) with a time-tolerance of 2 seconds instead:
java -jar Sync.jar −−nocrc −−time:2000 "C:\Original" "C:\Backup"
As in example 1, but always rename and synchronize time of matched target files, overwrite existing target files, and delete unmatched target files/directories:
java -jar Sync.jar −−force "C:\Original" "C:\Backup"
As in example 1, but synchronize only jpg and html files:
java -jar Sync.jar −−include:"*.{jpg,html}" "C:\Original" "C:\Backup"
As in example 5, but skip files that begin with a tilde '~':
java -jar Sync.jar −−include:"*.{jpg,html}" −−exclude:"~*" "C:\Original" "C:\Backup"

Further Examples

Synchronize target "C:\Backup" to look like source "C:\Original", matching files by (name,size,time,crc):
java -jar Sync.jar "C:\Original" "C:\Backup"
As in example 1, but never delete unmatched target files/directories:
java -jar Sync.jar −−delete:n "C:\Original" "C:\Backup"
As in example 1, but match files by (name,size,time) with a time-tolerance of 2 seconds instead:
java -jar Sync.jar −−nocrc −−time:2000 "C:\Original" "C:\Backup"
As in example 1, but always rename and synchronize time of matched target files, overwrite existing target files, and delete unmatched target files/directories:
java -jar Sync.jar −−force "C:\Original" "C:\Backup"
As in example 1, but synchronize only jpg and html files:
java -jar Sync.jar −−include:"*.{jpg,html}" "C:\Original" "C:\Backup"
As in example 5, but skip files that begin with a tilde '~':
java -jar Sync.jar −−include:"*.{jpg,html}" −−exclude:"~*" "C:\Original" "C:\Backup"
As in example 1, but skip "C:\Original\Temp1\*" and "C:\Original\Temp2\*":
java -jar Sync.jar −−path −−exclude:"{Temp1,Temp2}\\*" "C:\Original" "C:\Backup"
As in example 1, but skip any subfolder whose name is "Temp":
java -jar Sync.jar −−path −−exclude:"Temp\\*" −−exclude:"*\\Temp\\*" "C:\Original" "C:\Backup"
As in example 1, but skip bmp and mp3 files, ignoring case:
java -jar Sync.jar −−lower −−exclude:"*.{bmp,mp3}" "C:\Original" "C:\Backup"

Feedback?

Comments, suggestions, and bug reports are welcomed! Please send any feedback you have about Sync to email address , or visit the Sync homepage at http://syncdir.sourceforge.net/ to post a message, bug report, or download the latest version of Sync.