Switch to log4js with logj4 binding for logging

CPS/pom.xml

@@ -2,7 +2,7 @@
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>lu.list.itis.dkd.tui</groupId>
 	<artifactId>tulip-cps</artifactId>
-	<version>1.3.1</version>
+	<version>1.4.0</version>
 	<name>TULIP Complex Problem Solving</name>
 
 	<licenses>
@@ -59,6 +59,27 @@
   			<artifactId>jython-standalone</artifactId>
   			<version>2.7.1b3</version>
   		</dependency>
+		<dependency>
+			<groupId>org.slf4j</groupId>
+			<artifactId>slf4j-api</artifactId>
+			<version>1.7.23</version>
+		</dependency>
+		<dependency>
+			<groupId>org.apache.logging.log4j</groupId>
+			<artifactId>log4j-api</artifactId>
+			<version>2.8</version>
+		</dependency>
+  		<dependency>
+    		<groupId>org.apache.logging.log4j</groupId>
+    		<artifactId>log4j-core</artifactId>
+    		<version>2.8</version>
+  		</dependency>
+  		  <dependency>
+    		<groupId>org.apache.logging.log4j</groupId>
+    		<artifactId>log4j-slf4j-impl</artifactId>
+    		<version>2.8</version>
+    		<scope>runtime</scope>
+  		</dependency>
 		
 	</dependencies>
 	

CPS/src/lu/list/itis/dkd/tui/cps/system/Equation.java

@@ -27,9 +27,10 @@ import lu.list.itis.dkd.tui.cps.variable.Variable;
 
 import com.google.common.base.Preconditions;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import java.util.LinkedHashSet;
-import java.util.logging.Level;
-import java.util.logging.Logger;
 
 import javax.script.ScriptEngine;
 
@@ -49,7 +50,7 @@ public class Equation {
     private Executor scriptExecutor;
     private String script;
 
-    private static Logger LOGGER = Logger.getLogger(Equation.class.getSimpleName());
+    private static Logger LOGGER = LoggerFactory.getLogger(Equation.class.getSimpleName());
 
     /**
      * Constructor
@@ -103,7 +104,7 @@ public class Equation {
 
             scriptExecutor.eval(this.script);
         } catch (Exception exception) {
-            LOGGER.log(Level.SEVERE, "Error while evaluating script " + this.script, exception); //$NON-NLS-1$
+            LOGGER.error("Error while evaluating script {}", this.script, exception); //$NON-NLS-1$
         }
 
         dependentVariables = mapping.getDependentVariables();
@@ -111,18 +112,18 @@ public class Equation {
             try {
                 variable = scriptExecutor.get(variable);
             } catch (Exception exception) {
-                LOGGER.log(Level.SEVERE, "Error while retrieving variable " + variable.getName(), exception); //$NON-NLS-1$
+                LOGGER.error("Error while retrieving variable {}", variable.getName(), exception); //$NON-NLS-1$
             }
         }
 
         evaluationErrors = scriptExecutor.getExecutionErrors();
 
         if (evaluationErrors.length() > 0) {
-            LOGGER.log(Level.WARNING, "Error while evaluating equation :" + evaluationErrors); //$NON-NLS-1$
-            LOGGER.log(Level.WARNING, "Script =" + this.script); //$NON-NLS-1$
+            LOGGER.warn("Error while evaluating equation : {}", evaluationErrors); //$NON-NLS-1$
+            LOGGER.warn("Script = {}", this.script); //$NON-NLS-1$
             LinkedHashSet<Variable> independentVariables = mapping.getIndependentVariables();
             for (Variable variable : independentVariables) {
-                LOGGER.log(Level.INFO, variable.getName() + " = " + variable.getValue()); //$NON-NLS-1$
+                LOGGER.trace("{} = {}", variable.getName(), variable.getValue()); //$NON-NLS-1$
             }
         }
     }

CPS/src/lu/list/itis/dkd/tui/cps/system/executor/Executor.java

@@ -3,15 +3,17 @@ package lu.list.itis.dkd.tui.cps.system.executor;
 import lu.list.itis.dkd.tui.cps.system.Import;
 import lu.list.itis.dkd.tui.cps.variable.Variable;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import java.io.CharArrayWriter;
 import java.util.List;
 import java.util.Properties;
-import java.util.logging.Logger;
 
 abstract public class Executor {
     protected CharArrayWriter executionErrors;
 
-    private static Logger LOGGER = Logger.getLogger(Executor.class.getSimpleName());
+    private static Logger LOGGER = LoggerFactory.getLogger(Executor.class.getSimpleName());
 
     public Executor() {
         executionErrors = new CharArrayWriter();
@@ -32,7 +34,7 @@ abstract public class Executor {
 
     @SuppressWarnings("unused")
     public void resolve(List<Import> imports) {
-        LOGGER.warning("Imports not supported by Executor!"); //$NON-NLS-1$
+        LOGGER.warn("Imports not supported by Executor!"); //$NON-NLS-1$
     }
 
     abstract public void set(Variable variable);

CPS/src/lu/list/itis/dkd/tui/cps/system/executor/JavascriptExecutor.java

@@ -2,8 +2,10 @@ package lu.list.itis.dkd.tui.cps.system.executor;
 
 import lu.list.itis.dkd.tui.cps.variable.Variable;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import java.util.Properties;
-import java.util.logging.Logger;
 
 import javax.script.ScriptEngine;
 import javax.script.ScriptEngineManager;
@@ -13,7 +15,7 @@ public class JavascriptExecutor extends Executor {
     private ScriptEngine engine;
     private Object result;
 
-    private static Logger LOGGER = Logger.getLogger(JavascriptExecutor.class.getSimpleName());
+    private static Logger LOGGER = LoggerFactory.getLogger(JavascriptExecutor.class.getSimpleName());
 
     public JavascriptExecutor() {
         engine = new ScriptEngineManager().getEngineByName("js"); //$NON-NLS-1$
@@ -28,14 +30,24 @@ public class JavascriptExecutor extends Executor {
     @Override
     public void set(Variable variable) {
         engine.put(variable.getName(), variable.getValue());
+        if (LOGGER.isTraceEnabled()) {
+            LOGGER.trace("Parameter {} = {}", variable.getName(), variable.getValue()); //$NON-NLS-1$
+        }
     }
 
     @Override
     public boolean eval(String script) {
         try {
+            long elapsed = System.currentTimeMillis();
             result = engine.eval(script);
+            elapsed = System.currentTimeMillis() - elapsed;
+            if (LOGGER.isTraceEnabled()) {
+                LOGGER.trace("Eval => {} | took {} ms!", script, elapsed); //$NON-NLS-1$
+            }
         } catch (ScriptException exception) {
             this.executionErrors.append(exception.toString());
+            LOGGER.warn("Failed to eval script => {}", script); //$NON-NLS-1$
+            LOGGER.warn("Caused by...", exception); //$NON-NLS-1$
             return false;
         }
         return true;
@@ -44,6 +56,9 @@ public class JavascriptExecutor extends Executor {
     @Override
     public Variable get(Variable variable) {
         variable.setValue(result);
+        if (LOGGER.isTraceEnabled()) {
+            LOGGER.trace("Result {} = {}", variable.getName(), result); //$NON-NLS-1$
+        }
         return variable;
     }
 }

CPS/src/lu/list/itis/dkd/tui/cps/system/executor/OctaveExecutor.java

@@ -2,6 +2,9 @@ package lu.list.itis.dkd.tui.cps.system.executor;
 
 import lu.list.itis.dkd.tui.cps.variable.Variable;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import java.io.File;
 import java.util.Properties;
 
@@ -16,14 +19,25 @@ public class OctaveExecutor extends Executor {
     private static final String SCRIPT_ENGINE_EXECUTABLE = "octave.executable"; //$NON-NLS-1$
     private static final String SCRIPT_ENGINE_WORKING_DIR = "octave.workingDir"; //$NON-NLS-1$
 
-    // private static Logger LOGGER = Logger.getLogger(OctaveExecutor.class.getSimpleName());
+    private static final String DEFAULT_EXECUTABLE = "/opt/local/bin/octave"; //$NON-NLS-1$
+    private static final String DEFAULT_WORKING_DIR = "octave"; //$NON-NLS-1$
+
+    private static Logger LOGGER = LoggerFactory.getLogger(OctaveExecutor.class.getSimpleName());
 
     public OctaveExecutor(Properties properties) {
         super(properties);
 
         OctaveEngineFactory engineFactory = new OctaveEngineFactory();
-        engineFactory.setOctaveProgram(new File(properties.getProperty(SCRIPT_ENGINE_EXECUTABLE, "/opt/local/bin/octave"))); //$NON-NLS-1$
-        engineFactory.setWorkingDir(new File(properties.getProperty(SCRIPT_ENGINE_WORKING_DIR, "octave"))); //$NON-NLS-1$
+        String executable = properties.getProperty(SCRIPT_ENGINE_EXECUTABLE, DEFAULT_EXECUTABLE);
+        String workingDir = properties.getProperty(SCRIPT_ENGINE_WORKING_DIR, DEFAULT_WORKING_DIR);
+
+        engineFactory.setOctaveProgram(new File(executable));
+        engineFactory.setWorkingDir(new File(workingDir));
+
+        if (LOGGER.isInfoEnabled()) {
+            LOGGER.info("Octave Executable  : {}", executable); //$NON-NLS-1$
+            LOGGER.info("Octave Working Dir : {}", workingDir); //$NON-NLS-1$
+        }
 
         engine = engineFactory.getScriptEngine();
         engine.setErrorWriter(this.executionErrors);
@@ -33,11 +47,19 @@ public class OctaveExecutor extends Executor {
     public void set(Variable variable) {
         Double numericValue = Double.valueOf(variable.getValue().toString());
         engine.put(variable.getName(), Octave.scalar(numericValue));
+        if (LOGGER.isTraceEnabled()) {
+            LOGGER.trace("Parameter {} = {}", variable.getName(), variable.getValue()); //$NON-NLS-1$
+        }
     }
 
     @Override
     public boolean eval(String script) {
+        long elapsed = System.currentTimeMillis();
         engine.eval(script);
+        elapsed = System.currentTimeMillis() - elapsed;
+        if (LOGGER.isTraceEnabled()) {
+            LOGGER.trace("Eval => {} | took {} ms!", script, elapsed); //$NON-NLS-1$
+        }
         return true;
     }
 
@@ -45,6 +67,10 @@ public class OctaveExecutor extends Executor {
     public Variable get(Variable variable) {
         OctaveDouble result = engine.get(OctaveDouble.class, variable.getName());
         variable.setValue(result.get(1));
+        if (LOGGER.isTraceEnabled()) {
+            LOGGER.trace("Result {} = {}", variable.getName(), result.get(1)); //$NON-NLS-1$
+        }
+
         return variable;
     }
 

CPS/src/lu/list/itis/dkd/tui/cps/system/executor/PythonExecutor.java

@@ -7,11 +7,11 @@ import org.python.core.PyFloat;
 import org.python.core.PyObject;
 import org.python.core.PyTuple;
 import org.python.util.PythonInterpreter;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.util.List;
 import java.util.Properties;
-import java.util.logging.Level;
-import java.util.logging.Logger;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -22,7 +22,7 @@ public class PythonExecutor extends Executor {
 
     private static final Pattern TUPLE_PATTERN = Pattern.compile("^([a-z0-9_]+)\\.([a-z0-9_]+)", Pattern.CASE_INSENSITIVE); //$NON-NLS-1$
 
-    private static Logger LOGGER = Logger.getLogger(PythonExecutor.class.getSimpleName());
+    private static Logger LOGGER = LoggerFactory.getLogger(PythonExecutor.class.getSimpleName());
 
     public PythonExecutor(Properties properties) {
         super(properties);
@@ -41,8 +41,7 @@ public class PythonExecutor extends Executor {
             StringBuilder importBuilder = new StringBuilder("from "); //$NON-NLS-1$
             importBuilder.append(declaration.getFrom()).append(" import ").append(declaration.getFunction()); //$NON-NLS-1$
             engine.exec(importBuilder.toString());
-
-            LOGGER.log(Level.INFO, importBuilder.toString());
+            LOGGER.info(importBuilder.toString());
         }
     }
 
@@ -50,11 +49,19 @@ public class PythonExecutor extends Executor {
     public void set(Variable variable) {
         Double numericValue = Double.valueOf(variable.getValue().toString());
         engine.set(variable.getName(), new PyFloat(numericValue));
+        if (LOGGER.isTraceEnabled()) {
+            LOGGER.trace("Parameter {} = {}", variable.getName(), variable.getValue()); //$NON-NLS-1$
+        }
     }
 
     @Override
     public boolean eval(String script) {
+        long elapsed = System.currentTimeMillis();
         engine.exec(script);
+        elapsed = System.currentTimeMillis() - elapsed;
+        if (LOGGER.isTraceEnabled()) {
+            LOGGER.trace("Eval => {} | took {} ms!", script, elapsed); //$NON-NLS-1$
+        }
         return true;
     }
 
@@ -67,9 +74,16 @@ public class PythonExecutor extends Executor {
             if (tupleMatcher.matches()) {
                 PyTuple tuple = (PyTuple) engine.get(tupleMatcher.group(1));
                 result = tuple.__getattr__(tupleMatcher.group(2));
+                if (LOGGER.isTraceEnabled()) {
+                    LOGGER.trace("Result {} = {}.{} = {}", variable.getName(), tupleMatcher.group(1), tupleMatcher.group(2), result); //$NON-NLS-1$
+                }
             }
         } else {
             result = engine.get(variable.getName());
+            if (LOGGER.isTraceEnabled()) {
+                LOGGER.trace("Result {} = {}", variable.getName(), result); //$NON-NLS-1$
+            }
+
         }
         variable.setValue((result != null) ? result.__tojava__(Double.class) : null);
         return variable;

CPS/src/lu/list/itis/dkd/tui/cps/utility/Externalization.java

@@ -32,12 +32,13 @@ public class Externalization extends NLS {
     private static final String BUNDLE_NAME = "lu.list.itis.dkd.tui.cps.utility.externalization";
 
     public static String EXECUTOR_CLASS;
-    public static String VARIABLE_CLASS;
+    public static String NUMERIC_VARIABLE_CLASS;
+    public static String LOGIC_VARIABLE_CLASS;
 
     public static String EQUATION_ELEMENT;
     public static String EQUATIONS_ELEMENT;
     public static String INVOKE_ELEMENT;
-    public static String NAME_ELEMENT;
+    public static String NAME_ATTRIBUTE;
     public static String OUTPUT_ELEMENT;
     public static String OUTPUTS_ELEMENT;
     public static String PARAMETER_ELEMENT;
@@ -52,8 +53,15 @@ public class Externalization extends NLS {
     public static String FROM_ATTRIBUTE;
     public static String IMPORTS_ELEMENT;
     public static String SYSTEM_ELEMENT;
+    public static String TYPE_ATTRIBUTE;
     public static String UNIT_ATTRIBUTE;
-    public static String UNIT_ELEMENT;
+    public static String MINIMUM_ATTRIBUTE;
+    public static String MAXIMUM_ATTRIBUTE;
+    public static String SCALE_ATTRIBUTE;
+    public static String DECIMALS_ATTRIBUTE;
+
+    public static final String LOGIC_TYPE = "logic";
+    public static final String NUMERIC_TYPE = "numeric";
 
     static {
         // initialize resource bundle

CPS/src/lu/list/itis/dkd/tui/cps/utility/externalization.properties

 EXECUTOR_CLASS=executor.class
-VARIABLE_CLASS=variable.class
-EQUATION_ELEMENT=equation
+NUMERIC_VARIABLE_CLASS=numeric.variable.class
+LOGIC_VARIABLE_CLASS=logic.variable.class
+
 EQUATIONS_ELEMENT=equations
+EQUATION_ELEMENT=equation
 INVOKE_ELEMENT=invoke
-NAME_ELEMENT=name
-OUTPUT_ELEMENT=output
+NAME_ATTRIBUTE=name
 OUTPUTS_ELEMENT=outputs
+OUTPUT_ELEMENT=output
 PARAMETER_ELEMENT=parameter
+TYPE_ATTRIBUTE=type
 INITIAL_ATTRIBUTE=initial
+MINIMUM_ATTRIBUTE=minimum
+MAXIMUM_ATTRIBUTE=maximum
+SCALE_ATTRIBUTE=scale
+DECIMALS_ATTRIBUTE=decimals
 PARAMETERS_ELEMENT=parameters
 PERIODIC_ATTRIBUTE=periodic
 RESULT_ELEMENT=result
 EQUATE_ATTRIBUTE=equate
 RESULTS_ELEMENT=results
+IMPORTS_ELEMENT=imports
 IMPORT_ELEMENT=import
 FUNCTION_ATTRIBUTE=function
 FROM_ATTRIBUTE=from
-IMPORTS_ELEMENT=imports
 SYSTEM_ELEMENT=system
-UNIT_ATTRIBUTE=unit
-UNIT_ELEMENT=unit
\ No newline at end of file
+UNIT_ATTRIBUTE=unit
\ No newline at end of file

CPS/src/lu/list/itis/dkd/tui/cps/variable/BooleanVariable.java

@@ -22,6 +22,7 @@ package lu.list.itis.dkd.tui.cps.variable;
 
 import lu.list.itis.dkd.tui.cps.InputChangeListener;
 import lu.list.itis.dkd.tui.cps.InputEvent;
+import lu.list.itis.dkd.tui.cps.utility.Externalization;
 
 import java.util.Vector;
 
@@ -39,7 +40,7 @@ public class BooleanVariable extends Variable {
      * @param value
      */
     public BooleanVariable(String name, boolean value) {
-        super(name, "boolean"); //$NON-NLS-1$
+        super(Externalization.LOGIC_TYPE, name, "boolean"); //$NON-NLS-1$
 
         this.value = value;
     }
@@ -56,7 +57,7 @@ public class BooleanVariable extends Variable {
         if (value instanceof Boolean) {
             this.value = (Boolean) value;
         } else {
-            this.value = Boolean.parseBoolean(value.toString());
+            this.value = (Boolean) valueFromString(value.toString());
         }
 
         for (InputChangeListener listener : listeners) {
@@ -71,4 +72,10 @@ public class BooleanVariable extends Variable {
         variable.listeners = new Vector<>(listeners);
         return variable;
     }
+
+    /** {@inheritDoc} */
+    @Override
+    public Object valueFromString(String stringValue) {
+        return Boolean.parseBoolean(stringValue);
+    }
 }
\ No newline at end of file

CPS/src/lu/list/itis/dkd/tui/cps/variable/NumericalVariable.java

@@ -24,13 +24,14 @@ import lu.list.itis.dkd.dbc.annotation.NonNullByDefault;
 import lu.list.itis.dkd.dbc.annotation.Nullable;
 import lu.list.itis.dkd.tui.cps.InputChangeListener;
 import lu.list.itis.dkd.tui.cps.InputEvent;
+import lu.list.itis.dkd.tui.cps.utility.Externalization;
 
 import org.jdom2.Element;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.text.DecimalFormat;
 import java.util.Vector;
-import java.util.logging.Level;
-import java.util.logging.Logger;
 
 /**
  * Class implementing numerical variables as handled by the {@link System}.
@@ -38,12 +39,19 @@ import java.util.logging.Logger;
  * @author Eric Tobias [eric.tobias@list.lu]
  * @since 1.0
  * @version 1.3.0
+ * @param <T>
  */
 @NonNullByDefault
 public class NumericalVariable extends Variable {
     protected double value;
+    protected double minValue;
+    protected double maxValue;
+    protected double scale;
+
     private DecimalFormat format;
 
+    private static final Logger logger = LoggerFactory.getLogger(NumericalVariable.class.getSimpleName());
+
     /**
      * Constructor resorting to the super constructor to initialise the name and unit and locally
      * initialising the numerical value.
@@ -55,13 +63,17 @@ public class NumericalVariable extends Variable {
      * @param value
      *        The value held by the variable.
      */
-    public NumericalVariable(String name, String unit, double value) {
-        super(name, unit);
+    public NumericalVariable(String name, String unit, Double value) {
+        super(Externalization.NUMERIC_TYPE, name, unit);
         this.value = value;
 
         format = new DecimalFormat();
         format.setDecimalSeparatorAlwaysShown(false);
         format.setGroupingUsed(false);
+
+        minValue = Double.MIN_VALUE;
+        maxValue = Double.MAX_VALUE;
+        scale = 1;
     }
 
     /**
@@ -73,7 +85,7 @@ public class NumericalVariable extends Variable {
      *        necessary information to initialize the variable.
      */
     public NumericalVariable(Element rootElement) {
-        super(rootElement.getChildText("name"), rootElement.getChildText("unit")); //$NON-NLS-1$ //$NON-NLS-2$
+        super(Externalization.NUMERIC_TYPE, rootElement.getChildText("name"), rootElement.getChildText("unit")); //$NON-NLS-1$ //$NON-NLS-2$
         this.value = Double.parseDouble(rootElement.getChildText("value")); //$NON-NLS-1$
 
         format = new DecimalFormat();
@@ -82,12 +94,6 @@ public class NumericalVariable extends Variable {
 
     }
 
-    /** {@inheritDoc} */
-    @Override
-    public Double getValue() {
-        return value;
-    }
-
     /**
      * {@inheritDoc}<br>
      * <br>
@@ -141,19 +147,91 @@ public class NumericalVariable extends Variable {
     /** {@inheritDoc} */
     @Override
     public void setValue(Object value) {
-        try {
-            this.value = Double.parseDouble(value.toString());
+        Double newValue;
+        newValue = (Double) this.valueFromString(value.toString());
+        if (newValue < this.minValue)
+            this.value = this.minValue;
+        else if (newValue > this.maxValue)
+            this.value = this.maxValue;
+        else
+            this.value = newValue;
 
-            for (InputChangeListener listener : listeners) {
-                listener.inputChanged(new InputEvent(this));
-            }
-        } catch (NumberFormatException e) {
-            Logger.getLogger(NumericalVariable.class.getSimpleName()).log(Level.SEVERE, "The provided value (" + value.toString() + ") does not match " //$NON-NLS-1$ //$NON-NLS-2$
-                            + "the value stored by this variable instance.", e); //$NON-NLS-1$
-            throw e;
+        InputEvent event = new InputEvent(this);
+        for (InputChangeListener listener : listeners) {
+            // listener.inputChanged(new InputEvent(this));
+            listener.inputChanged(event);
         }
-        // EventLogger.getInstance().addNumericalVariableInfo(this.name, format.format(value),
-        // unit);
+    }
+
+    /** {@inheritDoc} */
+    @Override
+    public Object getValue() {
+        return this.value;
+    }
+
+    /**
+     * 
+     * @param value
+     *        specifies the new minimum value for this variable
+     */
+    public void setMinValue(double value) {
+        this.minValue = value;
+    }
+
+    /**
+     * 
+     * @return the minimum value defined for this variable. If not previously set, the minimum value
+     *         will be Double.MIN_VALUE
+     */
+    public double getMinValue() {
+        return this.minValue;
+    }
+
+    /**
+     * 
+     * @param value
+     *        specifies the new maximum value for this variable
+     */
+    public void setMaxValue(double value) {
+        this.maxValue = value;
+    }
+
+    /**
+     * 
+     * @return the maximum value defined for this variable. If not previously set, the minimum value
+     *         will be Double.MAX_VALUE
+     */
+    public double getMaxValue() {
+        return this.maxValue;
+    }
+
+    /**
+     * 
+     * @param scale
+     *        specifies the display scale for this variable.
+     */
+
+    public void setScale(double scale) {
+        this.scale = scale;
+    }
+
+    /**
+     * 
+     * @return the scale to be used when displaying the value of this variable.
+     */
+
+    public double getScale() {
+        return this.scale;
+    }
+
+    /**
+     * 
+     * @param decimals
+     *        specifies the number of decimals when displaying this variable.
+     */
+
+    public void setNumberOfDecimals(int decimals) {
+        this.format.setMaximumFractionDigits(decimals);
     }
 
     /** {@inheritDoc} */
@@ -161,7 +239,23 @@ public class NumericalVariable extends Variable {
     public NumericalVariable clone() {
         NumericalVariable variable = new NumericalVariable(name, unit, value);
         variable.format = format;
+        variable.minValue = minValue;
+        variable.maxValue = maxValue;
+        variable.scale = scale;
         variable.listeners = new Vector<>(listeners);
         return variable;
     }
+
+    /** {@inheritDoc} */
+    @Override
+    public Object valueFromString(String stringValue) {
+        Double newValue = Double.valueOf(0);
+        try {
+            newValue = Double.parseDouble(stringValue);
+        } catch (NumberFormatException e) {
+            logger.error("The provided value ({}) does not match the format stored by this variable instance.", stringValue, e); //$NON-NLS-1$
+            throw e;
+        }
+        return newValue;
+    }
 }
\ No newline at end of file

CPS/src/lu/list/itis/dkd/tui/cps/variable/Variable.java

@@ -32,9 +32,12 @@ import java.util.Vector;
  * @author Eric Tobias [eric.tobias@list.lu]
  * @since 1.0
  * @version 1.3.0
+ * @param <T>
  */
 @NonNullByDefault
 public abstract class Variable implements Cloneable {
+    /** The data type of the variable. */
+    protected String type;
     /** The name of the variable. */
     protected String name;
     /** The unit the variable is given in. */
@@ -54,12 +57,22 @@ public abstract class Variable implements Cloneable {
      * @param unit
      *        The unit the variable is given in.
      */
-    public Variable(String name, String unit) {
+    public Variable(String type, String name, String unit) {
+        this.type = type;
         this.name = name;
         this.unit = unit;
         listeners = new Vector<>();
     }
 
+    /**
+     * Simple getter method for unit.
+     * 
+     * @return The value of unit.
+     */
+    public String getType() {
+        return type;
+    }
+
     /**
      * Simple getter method for name.
      * 
@@ -136,7 +149,9 @@ public abstract class Variable implements Cloneable {
         if (object instanceof Variable) {
             Variable variable = (Variable) object;
 
-            if (name.equals(variable.getName()) && unit.equals(variable.getUnit())) {
+            if (type.equals(variable.getType()) &&
+                            name.equals(variable.getName()) &&
+                            unit.equals(variable.getUnit())) {
                 return true;
             }
         }
@@ -157,4 +172,14 @@ public abstract class Variable implements Cloneable {
     /** {@inheritDoc} */
     @Override
     public abstract Variable clone();
+
+    /**
+     * 
+     * @param stringValue
+     *        specifies a stringified version of the value to be converted
+     * @return
+     */
+
+    public abstract Object valueFromString(String stringValue);
+
 }
\ No newline at end of file

CPS/src/lu/list/itis/dkd/tui/cps/variable/tangible/TangibleNumericalVariable.java

@@ -41,7 +41,7 @@ import org.jdom2.Element;
  * @version 1.3.0
  */
 @NonNullByDefault
-public class TangibleNumericalVariable extends NumericalVariable implements ContextEventListener, InformationProvider<String> {
+public class