org.eclipse.linuxtools.tmf.core/src/org/eclipse/linuxtools/tmf/core/statevalue/ITmfStateValue.java

   1 /*******************************************************************************
   2  * Copyright (c) 2012 Ericsson
   3  *
   4  * All rights reserved. This program and the accompanying materials are
   5  * made available under the terms of the Eclipse Public License v1.0 which
   6  * accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *   Alexandre Montplaisir - Initial API
  11  ******************************************************************************/
  12
  13 package org.eclipse.linuxtools.tmf.core.statevalue;
  14
  15 import org.eclipse.linuxtools.tmf.core.exceptions.StateValueTypeException;
  16
  17
  18 /**
  19  * This is the interface for using state values and reading their contents.
  20  *
  21  * @author alexmont
  22  *
  23  */
  24 public interface ITmfStateValue {
  25
  26     public static final byte TYPE_NULL = -1;
  27     public static final byte TYPE_INTEGER = 0;
  28     public static final byte TYPE_STRING = 1;
  29
  30     /**
  31      * Each implementation has to supply a "type" number. This will get written
  32      * as-is in the History file to recognize the type, so it needs to be unique
  33      *
  34      * @return The unique "int8" assigned to this state value type
  35      */
  36     public byte getType();
  37
  38     /**
  39      * Only "null values" should return true here
  40      *
  41      * @return True if this type of SV is considered "null", false if it
  42      *         contains a real value.
  43      */
  44     public boolean isNull();
  45
  46     /**
  47      * Read the contained value as an 'int' primitive
  48      *
  49      * @return The integer contained in the state value
  50      * @throws StateValueTypeException
  51      *             If the contained value cannot be read as an integer
  52      */
  53     public int unboxInt() throws StateValueTypeException;
  54
  55     /**
  56      * Read the contained value as a String
  57      *
  58      * @return The String contained in the state value
  59      * @throws StateValueTypeException
  60      *             If the contained value cannot be read as a String
  61      */
  62     public String unboxStr() throws StateValueTypeException;
  63 }