BigDecimal Class plus()方法 (BigDecimal Class plus() method)
Syntax:
句法:
    public BigDecimal plus();
public BigDecimal plus(MathContext ma_co);
- plus() method is available in java.math package. - plus()方法在java.math包中可用。 
- plus() method is used to get the value with (+) representation of this BigDecimal. - plus()方法用于获取此BigDecimal的(+)表示形式的值。 
- plus(MathContext ma_co) method is used to get the value with (+) representation of this BigDecimal along with rounding based on the given MathContext settings. - plus(MathContext ma_co)方法用于获取此BigDecimal的(+)表示形式的值,并根据给定的MathContext设置进行舍入。 
- These methods may throw an exception at the time of + representation of an object. - 这些方法在对象的+表示时可能会引发异常。 - ArithmeticException: This exception may throw when the result is not accurate and set the rounding mode "UNNECESSARY". - ArithmeticException :当结果不正确并且将舍入模式设置为“ UNNECESSARY”时,可能会引发此异常。 
- These are non-static methods and it is accessible with class objects and if we try to access these methods with the class name then we will get an error. - 这些是非静态方法,可通过类对象访问,如果尝试使用类名访问这些方法,则会收到错误消息。 
Parameter(s):
参数:
- In the first case, plus(), - 在第一种情况下, plus() , - It does not accept any parameter.
 
- In the first case, plus(MathContext ma_co), - 在第一种情况下, plus(MathContext ma_co) , - MathContext ma_co – represents the context setting to use in rounding.
- MathContext ma_co –表示要舍入的上下文设置。
 
Return value:
返回值:
In both the cases, the return type of the method is BigDecimal,
在这两种情况下,方法的返回类型均为BigDecimal 。
- In the first case, it returns the plus value of this BigDecimal. - 在第一种情况下,它返回此BigDecimal的正值。 
- In the second case, it returns the plus value of this BigDecimal. with rounding based on the given context setting. - 在第二种情况下,它返回此BigDecimal的正值。 根据给定的上下文设置进行舍入。 
Example:
例:
// Java program to demonstrate the example 
// of plus() method of BigDecimal
import java.math.*;
public class PlusOfBD {
public static void main(String args[]) {
// Initialize two variables val1,
// val2 
String val1 = "-10.30";
int val2 = 4;
// Initialize two BigDecimal objects and
// one MathContext
BigDecimal b_dec1 = new BigDecimal(val1);
BigDecimal b_dec2 = new BigDecimal(val2);
MathContext ma_co = new MathContext(2, RoundingMode.CEILING);
System.out.println("plus(): ");
// returns the plus representation of this BigDecimal
// like (+ b_dec2)
BigDecimal plus = b_dec2.plus();
System.out.println("b_dec2.plus(): " + plus);
System.out.println(" ");
System.out.println("plus(MathContext): ");
// returns the plus representation of this BigDecimal
// (+b_dec1) and return the result based on the given
// context settings
plus = b_dec1.plus(ma_co);
System.out.println("b_dec1.plus(ma_co): " + plus);
}
}
Output
输出量
plus(): 
b_dec2.plus(): 4plus(MathContext): 
b_dec1.plus(ma_co): -10
翻译自: https://www.includehelp.com/java/bigdecimal-plus-method-with-example.aspx