formatedstring.java

geotools的源码

package uk.ac.leeds.ccg.geotools.misc;
import java.lang.*;

/** a utlity class to format numbers into strings.
 * specify a length and number of decimal places.
 * @author ian turton
 */
 
public class FormatedString {
	static boolean leadingzeros = false;
  public static final String format(double d){
    return format(""+d,2);
  }
  public final static String format(int i){
    return format(""+i,0);
  }
  public final static String format(int i,int len){
    return format(""+i,0,len);
  }
	public static final String format(String in){
		return format(in,2);
	}
  public final static String format(String in, int dp ,int len){
    StringBuffer sb = new StringBuffer();
    String s = format(in,dp).trim();
    int diff = len - s.length();
    
    for(int i=0;i < diff;i++) sb.append(" ");
    sb.append(s);
    return sb.toString();
  }
	public final static String format(String in,int dp){
	  int e1 = in.indexOf('e');
	  int e2 = in.indexOf('E');
	  int e = Math.max(e1,e2);
	  if(e>-1) in=expand(in,e);
		int i = in.lastIndexOf('.');
    if(i!=-1){
      String dec="";
			String num=in.substring(0,i);
			if(dp>0){
				if((i+dp+1)<in.length()){
					dec=in.substring(i,i+dp+1);
				}else{
					dec=in.substring(i);
					
				}
			}else{
				dec="";
			}
			while(dec.length()<dp+1)dec+="0";
			if(dp==0) dec="";
			if(!leadingzeros){
				char [] tmp = num.toCharArray();
				for(i=0;i<tmp.length-1;i++){	
					if(tmp[i]!='0'&&tmp[i]!=' ') break;
					if(tmp[i]=='0') tmp[i]=' ';
					if(tmp[i+1]=='.'&&tmp[i]==' ') tmp[i]='0';
				}
				num = new String(tmp);
			}
			return(num+dec);
    }else{
      String dec=".";
			while(dec.length()<dp+1)dec+="0";
			if(dp==0) dec="";

			if(!leadingzeros){
				char [] tmp = in.toCharArray();
				for(i=0;i<tmp.length-1;i++){	
					if(tmp[i]!='0'&&tmp[i]!=' ') break;
					if(tmp[i]=='0') tmp[i]=' ';
					if(tmp[i+1]=='.'&&tmp[i]==' ') tmp[i]='0';
				}
				in = new String(tmp);
			}
      return(in+dec);
    }
	}
	private final static String expand(String s, int e){
	  String last = s.substring(e+1);
	  String start = s.substring(0,e);

    int pow = Integer.parseInt(last);
	  //System.out.println(start +" e "+last+" "+pow);
	  int i = start.indexOf('.');
	  if(i>0){
	    int d = start.length()-i-1;
	    String a = start.substring(0,i);
	    start = a + start.substring(i+1);
	    pow -= d;
    }
    for(i=0;i<pow;i++){
      start+="0";
    }
		for(i=pow;i<0;i++){
			start = "0"+start;
		}
    if(pow<0){
      int lp = start.length()+pow;
			//System.out.println(start+" x "+lp+" "+pow);
      start = start.substring(0,lp)+"."+start.substring(lp);
    }
    //System.out.println("->"+start);
    
    return start.trim();
  }
  public static void main(String args[]){
    System.out.println(args[0]+" "+FormatedString.format(args[0],6));
  }
}