reportbuilder/java/com/sun/star/report/ReportExpression.java

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  27 package com.sun.star.report;
  28
  29 /**
  30  * Expressions are simple computation components.
  31  *
  32  * Expressions are always assumed to be immutable. They are not allowed to
  33  * change their state and it is not guaranteed, in which order they get called.
  34  * If the expression has been called before, the last computed value will be
  35  * available from the datarow.
  36  *
  37  * This construct allows us to write expressions in the form
  38  * "Sum := Sum + Column".
  39  *
  40  * Multiple calls to getValue on the same expression instance must return the
  41  * same value (assuming that the datarow passed in is the same).
  42  */
  43 public interface ReportExpression
  44 {
  45
  46     void setParameters(Object[] parameters);
  47
  48     Object getParameters();
  49
  50     Object getValue(DataRow row);
  51 }