- /*
- * 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.
- */
-
- /* $Id$ */
-
- package org.apache.fop.fo.expr;
-
- import org.apache.fop.datatypes.Length;
- import org.apache.fop.datatypes.PercentBaseContext;
- import org.apache.fop.datatypes.Numeric;
- import org.apache.fop.fo.properties.Property;
- import org.apache.fop.fo.properties.TableColLength;
-
-
- /**
- * This class represent a node in a property expression tree.
- * It is created when an operation involve relative expression and is used
- * to delay evaluation of the operation until the time where getNumericValue()
- * or getValue() is called.
- */
- public class RelativeNumericProperty extends Property implements Length {
- /** ADDITION */
- public static final int ADDITION = 1;
- /** SUBTRACTION */
- public static final int SUBTRACTION = 2;
- /** MULTIPLY */
- public static final int MULTIPLY = 3;
- /** DIVIDE */
- public static final int DIVIDE = 4;
- /** MODULO */
- public static final int MODULO = 5;
- /** NEGATE */
- public static final int NEGATE = 6;
- /** ABS */
- public static final int ABS = 7;
- /** MAX */
- public static final int MAX = 8;
- /** MIN */
- public static final int MIN = 9;
-
- // Used in the toString() method, indexed by operation id.
- private static String operations = " +-*/%";
-
- /**
- * The operation identifier.
- */
- private int operation;
- /**
- * The first (or only) operand.
- */
- private Numeric op1;
- /**
- * The second operand.
- */
- private Numeric op2 = null;
- /**
- * The dimension of the result.
- */
- private int dimension;
-
- /**
- * Constructor for a two argument operation.
- * @param operation the operation opcode: ADDITION, SUBTRACTION, ...
- * @param op1 the first operand.
- * @param op2 the second operand
- */
- public RelativeNumericProperty(int operation, Numeric op1, Numeric op2) {
- this.operation = operation;
- this.op1 = op1;
- this.op2 = op2;
- // Calculate the dimension. We can do now.
- switch (operation) {
- case MULTIPLY:
- dimension = op1.getDimension() + op2.getDimension();
- break;
- case DIVIDE:
- dimension = op1.getDimension() - op2.getDimension();
- break;
- default:
- dimension = op1.getDimension();
- }
- }
-
- /**
- * Constructor for a one argument operation.
- * @param operation the operation opcode: NEGATE, ABS
- * @param op the operand.
- */
- public RelativeNumericProperty(int operation, Numeric op) {
- this.operation = operation;
- this.op1 = op;
- this.dimension = op.getDimension();
- }
-
- /**
- * Return a resolved (calculated) Numeric with the value of the expression.
- * @param context Evaluation context
- * @return the resolved {@link Numeric} corresponding to the value of the expression
- * @throws PropertyException when an exception occur during evaluation.
- */
- private Numeric getResolved(PercentBaseContext context) throws PropertyException {
- switch (operation) {
- case ADDITION:
- return NumericOp.addition2(op1, op2, context);
- case SUBTRACTION:
- return NumericOp.subtraction2(op1, op2, context);
- case MULTIPLY:
- return NumericOp.multiply2(op1, op2, context);
- case DIVIDE:
- return NumericOp.divide2(op1, op2, context);
- case MODULO:
- return NumericOp.modulo2(op1, op2, context);
- case NEGATE:
- return NumericOp.negate2(op1, context);
- case ABS:
- return NumericOp.abs2(op1, context);
- case MAX:
- return NumericOp.max2(op1, op2, context);
- case MIN:
- return NumericOp.min2(op1, op2, context);
- default:
- throw new PropertyException("Unknown expr operation " + operation);
- }
- }
-
- /**
- * Return the resolved (calculated) value of the expression.
- * {@inheritDoc}
- */
- public double getNumericValue() throws PropertyException {
- return getResolved(null).getNumericValue(null);
- }
-
- /**
- * {@inheritDoc}
- */
- public double getNumericValue(PercentBaseContext context) throws PropertyException {
- return getResolved(context).getNumericValue(context);
- }
-
- /**
- * Return the dimension of the expression
- * @return numeric value as dimension
- */
- public int getDimension() {
- return dimension;
- }
-
- /**
- * Return false since an expression is only created when there is relative
- * numerics involved.
- * @return true if expression is absolute
- */
- public boolean isAbsolute() {
- return false;
- }
-
- /**
- * Cast this numeric as a Length.
- * @return numeric value as length
- */
- public Length getLength() {
- if (dimension == 1) {
- return this;
- }
- log.error("Can't create length with dimension " + dimension);
- return null;
- }
-
- /** @return numeric value */
- public Numeric getNumeric() {
- return this;
- }
-
- /**
- * {@inheritDoc}
- */
- public int getValue() {
- try {
- return (int) getNumericValue();
- } catch (PropertyException exc) {
- log.error(exc);
- }
- return 0;
- }
-
- /**
- * {@inheritDoc}
- */
- public int getValue(PercentBaseContext context) {
- try {
- return (int) getNumericValue(context);
- } catch (PropertyException exc) {
- log.error(exc);
- }
- return 0;
- }
-
- /**
- * Return the number of table units which are included in this length
- * specification. This will always be 0 unless the property specification
- * used the proportional-column-width() function (only on table column FOs).
- * <p>
- * If this value is not 0, the actual value of the Length cannot be known
- * without looking at all of the columns in the table to determine the value
- * of a "table-unit".
- *
- * @return The number of table units which are included in this length
- * specification.
- */
- public double getTableUnits() {
- double tu1 = 0.0, tu2 = 0.0;
- if (op1 instanceof RelativeNumericProperty) {
- tu1 = ((RelativeNumericProperty) op1).getTableUnits();
- } else if (op1 instanceof TableColLength) {
- tu1 = ((TableColLength) op1).getTableUnits();
- }
- if (op2 instanceof RelativeNumericProperty) {
- tu2 = ((RelativeNumericProperty) op2).getTableUnits();
- } else if (op2 instanceof TableColLength) {
- tu2 = ((TableColLength) op2).getTableUnits();
- }
- if (tu1 != 0.0 && tu2 != 0.0) {
- switch (operation) {
- case ADDITION:
- return tu1 + tu2;
- case SUBTRACTION:
- return tu1 - tu2;
- case MULTIPLY:
- return tu1 * tu2;
- case DIVIDE:
- return tu1 / tu2;
- case MODULO:
- return tu1 % tu2;
- case MIN:
- return Math.min(tu1, tu2);
- case MAX:
- return Math.max(tu1, tu2);
- default:
- assert false;
- }
- } else if (tu1 != 0.0) {
- switch (operation) {
- case NEGATE:
- return -tu1;
- case ABS:
- return Math.abs(tu1);
- default:
- return tu1;
- }
- } else if (tu2 != 0.0) {
- return tu2;
- }
- return 0.0;
- }
-
- /**
- * Return a string represention of the expression. Only used for debugging.
- * @return the string representation.
- */
- public String toString() {
- switch (operation) {
- case ADDITION: case SUBTRACTION:
- case DIVIDE: case MULTIPLY: case MODULO:
- return "(" + op1 + " " + operations.charAt(operation) + op2 + ")";
- case NEGATE:
- return "-" + op1;
- case MAX:
- return "max(" + op1 + ", " + op2 + ")";
- case MIN:
- return "min(" + op1 + ", " + op2 + ")";
- case ABS:
- return "abs(" + op1 + ")";
- default:
- return "unknown operation " + operation;
- }
- }
- }
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