NonNumericToWildcardFilter.java

package ca.sqlpower.sql;

public class NonNumericToWildcardFilter implements ColumnFilter {
    static final int STATE_NUMBERS=0;
    static final int STATE_NON_NUMBERS=1;
    char wildcard='%';
    boolean leadingWildcard=false;
    boolean trailingWildcard=false;

    public static ColumnFilter getInstance() {
		return (ColumnFilter)new NonNumericToWildcardFilter();
    }

    public void setWildcardCharacter(char wild) {
		wildcard=wild;
    }

    public void setForceLeadingWildcard(boolean enabled) {
		leadingWildcard=enabled;
    }

    public void setForceTrailingWildcard(boolean enabled) {
		trailingWildcard=enabled;
    }

    public String filter(String in) {
		char ch;
		int state=STATE_NUMBERS;
		StringBuffer out=new StringBuffer(in.length());
		
		for(int i=0; i<in.length(); i++) {
			ch=in.charAt(i);
			if(ch < '0' || ch > '9') {
				if(state==STATE_NUMBERS) {
					out.append(wildcard);
				}
				state=STATE_NON_NUMBERS;
			} else {
				out.append(ch);
				state=STATE_NUMBERS;
			}
		}
		
		if(out.charAt(0) != wildcard) {
			out.insert(0, wildcard);
		}
		
		if(out.charAt(out.length()-1) != wildcard) {
			out.append(wildcard);
		}
		
		return out.toString();
    }
}