public NumberExpression<Long> longValue() {
        return castToNum(Long.class);
    }
Create a {@code this.longValue()} expression

<p>Get the long expression of this numeric expression</p>

@return this.longValue()
@see java.lang.Number#longValue()
querydsl-core/src/main/java/com/querydsl/core/types/dsl/NumberExpression.java