question about prefix and suffix in java
I have an issue and i want your help!I have a specific REGEX which i have named it "unique" and i want to store the data that it gives me!! The prefix and the suffix of this regex!!so!!someone has told me to use
var prefix and
var suffix
but i don't know how to do it!
for your convinience i give u my xml for this regex
<reg name="unique">
<start><![CDATA[ <!-- 72 HOURS FORECASTS -->
]]></start>
<end><![CDATA[<!-- 72 HOURS FORECASTS -->]]></end>
</reg>
the code where i call this regex is
int k = 0;
for(Xml reg_is:fetchsite.child("site").child("regexps").children("reg")) {
if(reg_is.string("name").contains("unique")){
if(reg_开发者_开发百科is.child("start").content()=="")
error += "\tNo prefix reg.exp. given.\n";
else
prefix = HtmlMethods.removeBreaks(replaceVariables(reg_is.child("start").content()));
if(reg_is.child("end").content()=="")
error += "\tNo suffix reg.exp. given.\n";
else
suffix = HtmlMethods.removeBreaks(replaceVariables(reg_is.child("end").content()));
}
else{
poleis[k][0]= HtmlMethods.removeBreaks(reg_is.string("name"));
poleis[k][1] = HtmlMethods.removeBreaks(replaceVariables(reg_is.child("start").content()));
poleis[k][2] = HtmlMethods.removeBreaks(replaceVariables(reg_is.child("end").content()));
k++;
}
Some general comments on your code:
Using == to check for
String
equality is wrong! Use theequals()
method instead:reg_is.child("end").content().equals("")
Also, if you're comparing a
String
variable to a hard-codedString
, it's better to put the hard-coded String first. That way, if the variable is null, your program won't throw aNullPointerException
(because the hard codedString
can never be null!)"".equals(reg_is.child("end").content())
When doing a lot of
String
concatenation, it's more efficient to use aStringBuilder
:StringBuilder error = new StringBuilder(); error.append("\tNo prefix reg.exp. given.\n");
Like Oscar Reyes said, the safe thing to do with if statements is always use braces. If you add a line and forget to add the braces, you can waste hours tracking down bugs. I know it's happened to me before...
if(reg_is.child("start").content()==""){ error += "\tNo prefix reg.exp. given.\n"; } else { prefix = HtmlMethods.removeBreaks(replaceVariables(reg_is.child("start").content())); }
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