src/java/org/apache/fop/fo/expr/RelativeNumericProperty.java - xmlgraphics-fop - Git at Google

 /*
  * 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;
         }
     }
 }
	/*
	* 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;
	}
	}
	}