在数据库中存储Double.POSITIVE_INFINITY（EJB实体/ JBoss）

 //--

 @PrePersist  
 @PreUpdate  
 private void resetField() {

      if(field == Double.POSITIVE_INFINITY)
            field = somePredefinedValue;
 }

 //--

1e500

Float.MAX_VALUE

Float.MIN_VALUE

Double

Float.NaN

Float.POSITIVE_INFINITY

Float.NEGATIVE_INFINITY

NULL

/** The value I persist. See it is a Float; */
@Column(name = \"VALUE\")
private Float value;

/** the \'value complement\' that does the trick. */
@Column(name = \"VALUE_COMPLEMENT\") // You can see I\'ve added a new column in my table (it is a varchar)
private String valueComplement;

/**
 * value getter.
 * If my value is null, it could mean that it is a NaN or +/- infinity.
 * Then let\'s check the complement.
 */
public Float getValue() {
    if (value == null) {
        try {
            return Float.parseFloat(this.valueComplement);
        } catch (NumberFormatException e) {
            return null;
        }
    } else {
        return value;
    }
}

/**
 * value setter
 * If the given value is a NaN or Inf, set this.value to null 
 * and this.complement to the string representation of NaN or +/- Inf.
 */
public void setValue(Float value) {
    if (value != null && (value.isNaN() || value.isInfinite())) {
        this.valueComplement = value.toString();
        this.value = null;
    } else {
        this.value = value;
    }
}

| ID | LABEL                 | VALUE | VALUE_COMPLEMENT |
| -- | --------------------- | ----- | ---------------- |
|  1 | PI                    |  3.14 | NULL             |
|  2 | gravity acceleration  |  9.81 | NULL             |
|  3 | sqare root of -1      | NULL  | NaN              |
|  4 | log of 0              | NULL  | -Infinity        |