I get a query string from url by saying request.queryString() as -
supplyId=123456789b&search=true
I want to replace the value for "supplyId" with a new value. "supplyId" can come at any position in the query string. What would be the possible regular expression for this?
I wouldn't actually use regex for this, but string manipulation. Search for the position of "supplyId=" in the URL, then grab everything until the end of the string or "&", whichever comes first.
If you have to use a regex, try one of these:
(?<=supplyId=)[^&]+
supplyId=([^&]+)
Make sure case sensitivity is off. If you use the second pattern, the value you want will be in capture group 1.
= is the parameter name. You could just give your other parameters names that don't end in supplyid. But just for fun, you can solve that by adding \b to the beginning: (?<=\bsupplyId=)[^&]+ or \bsupplyId=([^&]+)\b for empty word? The delimiter & or query separator ? should be detected at front unless they are escaped.\b means a word boundary. It will prevent any letter, number, or underscore before supplyId, so & and ? will both trigger it. BTW, you can't escape those in a URL, unless you were talking about hexadecimal URL encoding. Any hex-encoded character would end in [0-9A-F], all of which would be blocked by \b as it should be. But as I said, it's basically moot. You're only matching the parameter name, which you yourself control.I think you should be able to do something like so:
String queryString = "supplyId=123456789b&search=true";
String anyStringIlike = "someValueIlike";
String newQueryString = queryString.replaceAll("supplyId=[^&]+","supplyId=" + anyStringIlike);
System.out.println(queryString);
System.out.println(newQueryString);
This should print:
supplyId=123456789b&search=true
supplyId=someValueIlike&search=true
abcdsupplyId=value ?In perl you could do something like this.
perl -le '@m = ( "garbare=i123123123asdlfkjsaf&supplyId=123456789b&search=true" =~ /supplyId=(\d+\w+)&/g ); print for @m
public static String updateQueryString (String queryString, String name, String value) {
if (queryString != null) {
queryString = queryString.replaceAll(name + "=.*?($|&)", "").replaceFirst("&$", "");
}
return addParameter(queryString, name, value);
}
public static String addParameter(queryString, name, value) {
return StringUtils.isEmpty(queryString) ? (name + "=" + value) : (queryString + "&" + name + "=" + value);
}
You call like: updateQueryString("supplyId=123456789b&search=true", "supplyId", "newValue");
output: search=true&supplyId=newValue
public class TestQueryStringValReplace {
public static String replace(String queryString, String propName, String newVal) {
return queryString.replaceAll(propName+"=[^&]+", propName+"=" + newVal);
}
public static void main(String[] args) {
Assert.assertEquals("supplyId=newVal&search=true", replace("supplyId=oldVal&search=true", "supplyId","newVal"));
Assert.assertEquals("supplyId=newVal", replace("supplyId=oldVal", "supplyId","newVal"));
Assert.assertEquals("search=true&supplyId=newVal&3rdprop=val", replace("search=true&supplyId=oldVal&3rdprop=val", "supplyId","newVal"));
}
}
