org.jgap.gp.function.ReadTerminal.java Source code

Introduction

Here is the source code for org.jgap.gp.function.ReadTerminal.java

Source

/*
 * This file is part of JGAP.
 *
 * JGAP offers a dual license model containing the LGPL as well as the MPL.
 *
 * For licensing information please see the file license.txt included with JGAP
 * or have a look at the top of class org.jgap.Chromosome which representatively
 * includes the JGAP license policy applicable for any file delivered with JGAP.
 */
package org.jgap.gp.function;

import org.apache.commons.lang.builder.*;
import org.jgap.*;
import org.jgap.gp.*;
import org.jgap.gp.impl.*;
import org.jgap.util.*;

/**
 * Reads a value from the internal memory.
 *
 * @author Klaus Meffert
 * @since 3.0
 */
public class ReadTerminal extends CommandGene implements ICloneable {
    /** String containing the CVS revision. Read out via reflection!*/
    private final static String CVS_REVISION = "$Revision: 1.15 $";

    /**
     * Symbolic name of the storage. Must correspond with a chosen name for
     * an other command working with memory (otherwise it would make no sense).
     */
    private String m_storageName;

    public ReadTerminal(final GPConfiguration a_conf, Class a_returnType, String a_storageName)
            throws InvalidConfigurationException {
        this(a_conf, a_returnType, a_storageName, 0);
    }

    public ReadTerminal(final GPConfiguration a_conf, Class a_returnType, String a_storageName, int a_subReturnType)
            throws InvalidConfigurationException {
        super(a_conf, 0, a_returnType, a_subReturnType, null);
        if (a_storageName == null || a_storageName.length() < 1) {
            throw new IllegalArgumentException("Memory name must not be empty!");
        }
        m_storageName = a_storageName;
    }

    public String toString() {
        return "read_from('" + m_storageName + "')";
    }

    /**
     * @return textual name of this command
     *
     * @author Klaus Meffert
     * @since 3.2
     */
    public String getName() {
        return "Read Terminal";
    }

    public int execute_int(ProgramChromosome c, int n, Object[] args) {
        check(c);
        // Read from memory.
        // -----------------
        try {
            Integer value = (Integer) getGPConfiguration().readFromMemory(m_storageName);
            if (value == null) {
                return 0;
            }
            return value.intValue();
        } catch (IllegalArgumentException iex) {
            throw new IllegalStateException("ReadTerminal without preceeding StoreTerminal");
        }
    }

    public long execute_long(ProgramChromosome c, int n, Object[] args) {
        check(c);
        try {
            return ((Long) getGPConfiguration().readFromMemory(m_storageName)).longValue();
        } catch (IllegalArgumentException iex) {
            throw new IllegalStateException("ReadTerminal without preceeding StoreTerminal");
        }
    }

    public double execute_double(ProgramChromosome c, int n, Object[] args) {
        check(c);
        try {
            return ((Double) getGPConfiguration().readFromMemory(m_storageName)).doubleValue();
        } catch (IllegalArgumentException iex) {
            throw new IllegalStateException("ReadTerminal without preceeding StoreTerminal");
        }
    }

    public float execute_float(ProgramChromosome c, int n, Object[] args) {
        check(c);
        try {
            return ((Float) getGPConfiguration().readFromMemory(m_storageName)).floatValue();
        } catch (IllegalArgumentException iex) {
            throw new IllegalStateException("ReadTerminal without preceeding StoreTerminal");
        }
    }

    public Object execute_object(ProgramChromosome c, int n, Object[] args) {
        check(c);
        try {
            return getGPConfiguration().readFromMemory(m_storageName);
        } catch (IllegalArgumentException iex) {
            throw new IllegalStateException("ReadTerminal without preceeding StoreTerminal");
        }
    }

    public boolean isValid(ProgramChromosome a_program) {
        return a_program.getIndividual().getCommandOfClass(0, StoreTerminal.class) >= 0;
    }

    /**
     * The compareTo-method.
     *
     * @param a_other the other object to compare
     * @return -1, 0, 1
     *
     * @author Klaus Meffert
     * @since 3.0
     */
    public int compareTo(Object a_other) {
        int result = super.compareTo(a_other);
        if (result != 0) {
            return result;
        }
        ReadTerminal other = (ReadTerminal) a_other;
        return new CompareToBuilder().append(m_storageName, other.m_storageName).toComparison();
    }

    /**
     * The equals-method.
     *
     * @param a_other the other object to compare
     * @return true if the objects are seen as equal
     *
     * @author Klaus Meffert
     * @since 3.0
     */
    public boolean equals(Object a_other) {
        try {
            ReadTerminal other = (ReadTerminal) a_other;
            return super.equals(a_other)
                    && new EqualsBuilder().append(m_storageName, other.m_storageName).isEquals();
        } catch (ClassCastException cex) {
            return false;
        }
    }

    /**
     * Clones the object. Simple and straight forward implementation here.
     *
     * @return cloned instance of this object
     *
     * @author Klaus Meffert
     * @since 3.4
     */
    public Object clone() {
        try {
            ReadTerminal result = new ReadTerminal(getGPConfiguration(), getReturnType(), m_storageName,
                    getSubReturnType());
            return result;
        } catch (Exception ex) {
            throw new CloneException(ex);
        }
    }
}