org.josql.expressions

类 ValueExpression

java.lang.Object

org.josql.expressions.Expression

org.josql.expressions.ValueExpression

直接已知子类:

Accessor, ArithmeticExpression, BindVariable, BooleanExpression, ConstantExpression, ExpressionList, Function, NewObjectExpression, SaveValue, SubQueryExpression

public abstract class ValueExpression
extends Expression

构造器概要

构造器

构造器和说明
ValueExpression()

方法概要

限定符和类型	方法和说明
abstract Object	evaluate(Object o, Query q)
Object	getValue(Object o, Query q) Get the value for this expression based upon the object passed in.

从类继承的方法 org.josql.expressions.Expression

getExpectedReturnType, hasFixedResult, init, isBracketed, isTrue, setBracketed, toString

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

构造器详细资料

ValueExpression

public ValueExpression()

方法详细资料

getValue

public Object getValue(Object o,
                       Query q)
                throws QueryExecutionException

从类复制的说明: Expression

Get the value for this expression based upon the object passed in. In general sub-classes should perform some operation on the object to generate their result. The Query object is provided so that sub-classes can gain access to the bind variables (if required), save values and so on. Whilst it may seem better to have the Query object as a member of this class this would then prevent the expression from being used separately from the Query (a design goal of JoSQL, i.e. independent processing).

指定者:

getValue 在类中 Expression

参数:

o - The current object that the expression should be evaluated on.

q - The Query object.

返回:

The value of the expression.

抛出:

QueryExecutionException - If something goes wrong with gaining the value.

evaluate

public abstract Object evaluate(Object o,
                                Query q)
                         throws QueryExecutionException

抛出:

QueryExecutionException