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java-math-BigDecimal.java
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79 lines (66 loc) · 2.51 KB
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------------------------
BigDecimal |
------------------------
# 静态变量
public final static int ROUND_UP = 0;
public final static int ROUND_DOWN = 1;
public final static int ROUND_CEILING = 2;
public final static int ROUND_FLOOR = 3;
public final static int ROUND_HALF_UP = 4;
public final static int ROUND_HALF_DOWN = 5;
public final static int ROUND_HALF_EVEN = 6;
public final static int ROUND_UNNECESSARY = 7;
* 各种舍入模式
# 构造函数
BigDecimal(char[] in)
BigDecimal(char[] in, int offset, int len)
BigDecimal(char[] in, int offset, int len, MathContext mc)
BigDecimal(char[] in, MathContext mc)
BigDecimal(double val)
BigDecimal(double val, MathContext mc)
BigDecimal(int val)
BigDecimal(int val, MathContext mc)
BigDecimal(String val)
BigDecimal(String val, MathContext mc)
BigDecimal(BigInteger val)
BigDecimal(BigInteger unscaledVal, int scale)
BigDecimal(BigInteger unscaledVal, int scale, MathContext mc)
BigDecimal(BigInteger val, MathContext mc)
BigDecimal(long val)
BigDecimal(long val, MathContext mc)
------------------------
BigDecimal-静态方法 |
------------------------
BigDecimal valueOf(double val)
BigDecimal valueOf(long val)
BigDecimal valueOf(long unscaledVal, int scale)
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BigDecimal-实例方法 |
------------------------
BigDecimal add(BigDecimal augend)
BigDecimal add(BigDecimal augend, MathContext mc)
BigDecimal subtract(BigDecimal subtrahend)
BigDecimal subtract(BigDecimal subtrahend, MathContext mc)
BigDecimal multiply(BigDecimal multiplicand)
BigDecimal multiply(BigDecimal multiplicand, MathContext mc)
BigDecimal divide(BigDecimal divisor)
BigDecimal divide(BigDecimal divisor, int roundingMode)
BigDecimal divide(BigDecimal divisor, int scale, int roundingMode)
BigDecimal divide(BigDecimal divisor, int scale, RoundingMode roundingMode)
BigDecimal divide(BigDecimal divisor, MathContext mc)
BigDecimal divide(BigDecimal divisor, RoundingMode roundingMode)
* 加减乘除
newScale 表示保留的小数位数
roundingMode 指定舍入模式(可以是int或者枚举)
mc 通过指定的 MathContext 处理精度和舍入
BigDecimal setScale(int newScale, int roundingMode)
* 格式化小数
newScale 表示保留的小数位数
roundingMode 舍入模式
String toString();
* 有必要时使用科学计数法
String toPlainString();
* 不使用任何指数
String toEngineeringString();
* 有必要时使用工程计数法
* 工程记数法是一种工程计算中经常使用的记录数字的方法, 与科学技术法类似. 但要求10的幂必须是3的倍数