org.apache.fop.datatypes.Numeric Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* $Id: Numeric.java 1805173 2017-08-16 10:50:04Z ssteiner $ */
package org.apache.fop.datatypes;
/**
* An interface for classes that can participate in numeric operations.
* All the numeric operation (+, -, *, ...) are expressed in terms of
* this Numeric interface.
* Numerics has a value (getNumericValue) and a dimension (getDimension).
* Numerics can be either absolute or relative. Relative numerics
* must be resolved against base value before the value can be used.
*
* To support relative numerics internally in the expression parser and
* during evaluation one additional methods exists: isAbsolute() which
* return true for absolute numerics and false for relative numerics.
*/
public interface Numeric {
/**
* Return the value of this Numeric
* @return the computed value.
*/
double getNumericValue();
/**
* Return the value of this Numeric
* @param context The context for the length calculation (for percentage based lengths)
* @return the computed value.
*/
double getNumericValue(PercentBaseContext context);
/**
* Return the dimension of this numeric. Plain numbers has a dimension of
* 0 and length has a dimension of 1. Other dimension can occur as a result
* of multiplications and divisions.
* @return the dimension.
*/
int getDimension();
/**
* Return true if the numeric is an absolute value. Relative values are
* percentages and table-column-units. All other numerics are absolute.
* @return true when the numeric is absolute.
*/
boolean isAbsolute();
/**
* Returns the value of this numeric as an int.
* @return the value as an integer.
*/
int getValue();
/**
* Returns the value of this numeric as an int.
* @param context the context for the length calculation (for percentage based lengths)
* @return the value as an integer.
*/
int getValue(PercentBaseContext context);
/**
* Return the resolved value. This method will be called during evaluation
* of the expression tree and relative numerics can then return a
* resolved absolute Numeric. Absolute numerics can just return themselves.
*
* @return A resolved value.
* @throws PropertyException
*/
//Numeric getResolved() throws PropertyException;
/**
* Return the enum value that is stored in this numeric.
* @return the enum value
*/
int getEnum();
}