StringLib.java

public class StringLib {

    public static String deleteChars(String str, String filter){

        boolean[] searchA=new boolean[128];
        char[] strA=str.toCharArray();
        char[] filterA=filter.toCharArray();

        int src, dst;

        for (int i=0;i<128;i++)
            searchA[i]=false;

        for (char c: filterA)
            searchA[c]=true;

        int length=str.length();

        for (src=dst=0;src<length;src++){
            if (searchA[strA[src]]==false){
                strA[dst]=strA[src];
                dst++;
            }

        }

        return new String(strA, 0, dst);

    }


    public static void main(String[] args){
        String str="Hello there";
        String filter="aeiou";

        System.out.println("'"+str+"' filtered with '"+filter+"' gives: "+deleteChars(str, filter));
    }
}