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Thread: loop generate?

  1. #1
    Junior Member
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    Default loop generate?

    hi. i have a hashmap like this:
    <key1, <1,3,6>>
    <key2, <2,4,6>>
    <key3, <4,7,9>>

    and i want output like this:

    key1, 1, key2, 2, key3, 4
    key1, 1, key2, 2, key3, 7
    key1, 1, key2, 2, key3, 9
    key1, 1, key2, 4, key3, 4
    key1, 1, key2, 4, key3, 7
    key1, 1, key2, 4, key3, 9
    key1, 1, key2, 6, key3, 4
    key1, 1, key2, 6, key3, 7
    key1, 1, key2, 6, key3, 9

    the problem is: the integer-array is variable as the number of keys also... but i need every combination. how do i do so?

  2. #2
    Member DanBrown's Avatar
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    Default Re: loop generate?

    and i want output like this:
    had you tried something to solve this problem.Sorry, we can help you only if you show some effort from your side.
    Thanks and Regards
    Dan Brown

    Common Java Mistakes

  3. #3
    mmm.. coffee JavaPF's Avatar
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    Default Re: loop generate?

    Please post something we can compile.
    Please use [highlight=Java] code [/highlight] tags when posting your code.
    Forum Tip: Add to peoples reputation by clicking the button on their useful posts.

  4. #4
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    Default Re: loop generate?

    hi. here is my code.
    the output is broken because the value is an array... is iterator the right way?! as said in the first post, i need to get every combination of the hash-values
    sample input-text looks like this:

    generic data = 1,2,3
    generic test = a,b
    generic rums = 12,13

    import java.io.BufferedReader; 
    import java.io.FileReader; 
    import java.util.*; 
    public class HashMapEx { 
        public static void main(String[] args) { 
            HashMap<String, String[]> metadata = new HashMap<String, String[]>();
            try { 
                // Opening file 
                // change "/Users/anyexample/input.txt" to path to your test file  
                BufferedReader in = new BufferedReader(new FileReader("test.txt"));
                // string buffer for file reading   
                String str;
                // reading line by line from file    
                while ((str = in.readLine()) != null) { 
                    //split string from metafile at "="
    				String[] splitarray = str.split("\\=");
    				//remove whitespaces from inputfile...
    				splitarray[0] = splitarray[0].trim();
    				splitarray[1] = splitarray[1].trim();
    				//test if splitted string starts with "generic"
    				//here also the hashmap is filled with the data from generics!
    				if (splitarray[0].startsWith("generic")){
    					String[] subsplit1 = splitarray[0].split("\\s+");
    					splitarray[0] = subsplit1[1];
    					String[] subsplit2 = splitarray[1].split("\\,");
    					//splitarray[1] = subsplit2;
    					for (int index=0; index<subsplit2.length; index++){
    							System.out.println(splitarray[0] + " " + subsplit2[index]);
    					// fill our hashmap with the wanted data...
    					metadata.put(splitarray[0], subsplit2);
    			System.out.println("found " + metadata.size() + " generics");
    			Set set = metadata.entrySet();
    			Iterator i = set.iterator();
    			      Map.Entry me = (Map.Entry)i.next();
    			      System.out.println(me.getKey() + " : " + me.getValue() );
                // Close buffered reader 
            } catch (Exception e) { 
    	    System.out.println("Datei nicht gefunden!");

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