Multiple methods to keep double two decimal digits Java preserves two decimal places

Import Java.text.DecimalFormat;  
DecimalFormat    DF   = new DecimalFormat ("##### #0.");   

Double D1 = 3.23456  
double d2 = 0.0;
Double d3 = 2.0;
Df.format (d1); 
Df.format (D2); 

3 results were: 

3.23
0.00 
2.00

Java preserves two-bit decimal questions:
mode one:
rounding  

double   f   =   111231.5585;  
BigDecimal   B   =   new   BigDecimal (f);  
Double   f1   =   B.setscale (2,   bigdecimal.round_half_up). Doublevalue ();  

Retain two decimal 
mode two:

java.text.DecimalFormat   df   =new   java.text.DecimalFormat ("#.00");  
Df.format (the number you want to format);
Example:

new Java.text.DecimalFormat ("#.00"). Format (3.1415926)
#.00 represents two-bit decimal #.0000 four-bit decimal, etc. ...

Mode three:

double d = 3.1415926;
string result = string. Format ("%.2f");
%.2f%. Indicates that the result of an arbitrary number of digits before the decimal point   2 represents a two-bit decimal format is a floating-point type

Mode IV:

NumberFormat ddf1=numberformat.getnumberinstance ();
The number of digits displayed by void setmaximumfractiondigits (int digits) digits is the maximum number of 
digits displayed after a decimal point is set for the formatted object, and the last bit shown is the rounded


import java.text.*; 
Import java.math.*; 
Class TT 
{public 
static void Main (String args[]) 
{double x=23.5455; 
NumberFormat ddf1=numberformat.getnumberinstance ();

Ddf1.setmaximumfractiondigits (2); 
String s= Ddf1.format (x); 
System.out.print (s); 
} 

Import java.text.*;
DecimalFormat df=new DecimalFormat (". # #");
Double d=1252.2563;
String St=df.format (d);
System.out.println (ST);