org.simantics.r.scl/src/org/simantics/r/scl/variable/RListLengthNode.java

   1 /*******************************************************************************\r
   2  * Copyright (c) 2014, 2016 Association for Decentralized Information Management\r
   3  * in Industry THTH ry.\r
   4  * All rights reserved. This program and the accompanying materials\r
   5  * are made available under the terms of the Eclipse Public License v1.0\r
   6  * which accompanies this distribution, and is available at\r
   7  * http://www.eclipse.org/legal/epl-v10.html\r
   8  *\r
   9  * Contributors:\r
  10  *     VTT Technical Research Centre of Finland - initial API and implementation\r
  11  *******************************************************************************/\r
  12 package org.simantics.r.scl.variable;\r
  13 \r
  14 import org.rosuda.REngine.REXP;\r
  15 import org.rosuda.REngine.REXPInteger;\r
  16 import org.rosuda.REngine.REXPMismatchException;\r
  17 \r
  18 public class RListLengthNode implements RVariableNode {\r
  19 \r
  20         RVariableNode parent;\r
  21         \r
  22         public RListLengthNode(RVariableNode parent) {\r
  23                 this.parent = parent;\r
  24         }\r
  25 \r
  26         @Override\r
  27         public REXP getValue() {\r
  28                 REXP parentValue = parent.getValue();\r
  29                 if (parentValue == null)\r
  30                         return null;\r
  31                 \r
  32                 try {\r
  33                         return new REXPInteger(parentValue.length());\r
  34                 } catch (REXPMismatchException e) {\r
  35                         return null;\r
  36                 }\r
  37         }\r
  38 \r
  39         @Override\r
  40         public String getName() {\r
  41                 return "length";\r
  42         }\r
  43 \r
  44         @Override\r
  45         public RVariableNode getParent() {\r
  46                 return parent;\r
  47         }\r
  48 }\r