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why hash map contains null

Puneet N Vyas
Ranch Hand

Joined: Sep 20, 2007
Posts: 61
can any one tell why the patternAsso hashmap contains null value even after being populated with values.

thanks for support

Christophe Verré

Joined: Nov 24, 2005
Posts: 14687

import java.lang.*;
import java.util.*;
import java.util.regex.*;

public class pattern
patternAsso's keys are made of values taken from patternStrings3.
patternStrings3 is made of p1[hh]+items[mm]+items[nn].
So it will look like "a.* aa", "a.* ab", "a.* ac"...
You forgot that p1 values contains a space. What you want to do is :

PS : try to remove the useless commented code next time

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Puneet N Vyas
Ranch Hand

Joined: Sep 20, 2007
Posts: 61
@thanks ,i have figured out the problem,sorry,i will follow the rules from next time..

thanks and regards
puneet vyas
I agree. Here's the link:
subject: why hash map contains null
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