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NumberFormat nf = NumberFormat.getIntegerInstance();
double v=12.6;
System.out.println(nf.format(v));
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DecimalFormat df=new DecimalFormat("#.##");
double v=12.126;
String s=df.format(v);
System.out.println(s);
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double v=-32.126;
String s=v+"";
System.out.println(s.substring(0, s.indexOf(".")+3));
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NumberFormat nf = NumberFormat.getPercentInstance();
double s=0.6145;
System.out.println(nf.format(s));
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