スキップしてメイン コンテンツに移動

投稿

Regex: Detect Repeated String Chunks

Target strings I am trying to detect string which contains repeated string pattern like below. .....ABCDABCDABCD..... "ABCD" is just an example, it can be any fixed length of string chunk. Solution Regex Thinking for a bit and finally reached the solution regex which meets my demand is something like below. (.{4,})\\1{3,} The above regex matches string whose length of the chunk is more than 4 and it should be repeated equal or more than 4 times. In more general regex is below (using pattern formatting). String.format("(.{%d,})\\1{%d,}", minChunkLen, times-1) Java Code Ok you know I am Java lover, I will show you full regex code with test cases. If you found any bugs on the code please feel free to comment. public static final boolean isRepeatedStrIn(String input, int minChunkLen, int times) { return input.matches(String.format("(.{%d,})\\1{%d,}", minChunkLen, times-1)); } package com.dukesoftware.utils.common; import java.util.Array

Check window.opener permission

Issue I tried to access some properties (or call methods) defined in http parent window via window.opener in pop-upped https window, which is created from the parent window. But it simply fails when accessing window.opener.a_property in the child window because the protocol is different between the child and parent window. e.g. http and https Remember this browser behavior is absolutely correct. The point of this post is how to avoid simply stopping javascript when accessing properties in window.opener. Browsers I confirmed this permission issue happens FireFox 17.0.1 and Internet Explore 9. Somehow Chrome doesn't complain it at all. the code simply passed. Solution In order to avoid this, I wrote the following conditions to detect the window.opener is accessible or not before accessing window.opener, but all of them don't return expected result at all. if(window.opener) // return true :( if(window.opener == undefined) // return true :( Finally I have reached at