src/org/diylc/core/AllowAllValidator.java

@@ -0,0 +1,13 @@
+package org.diylc.core;
+
+/**
+ * Validator that allows all values.
+ * 
+ * @author Branislav Stojkovic
+ */
+public class AllowAllValidator implements IPropertyValidator {
+
+	@Override
+	public void validate(Object value) throws ValidationException {
+	}
+}

src/org/diylc/core/ComponentState.java

@@ -0,0 +1,11 @@
+package org.diylc.core;
+
+/**
+ * Enumerates all possible states that a component can be in.
+ * 
+ * @author Branislav Stojkovic
+ */
+public enum ComponentState {
+
+	NORMAL, SELECTED, LOCKED, DRAGGING
+}

src/org/diylc/core/CreationMethod.java

@@ -0,0 +1,6 @@
+package org.diylc.core;
+
+public enum CreationMethod {
+
+	SINGLE_CLICK, POINT_BY_POINT;
+}

src/org/diylc/core/IDIYComponent.java

@@ -0,0 +1,122 @@
+package org.diylc.core;
+
+import java.awt.Graphics2D;
+import java.awt.Point;
+import java.io.Serializable;
+
+import org.diylc.core.annotations.ComponentDescriptor;
+import org.diylc.core.annotations.EditableProperty;
+
+/**
+ * Interface for component instance. Implementation classes of this interface
+ * will be instantiated by the application when component is added to the
+ * canvas. <br>
+ * <br>
+ * <b>Implementing classes should meet the following: </b>
+ * <ul>
+ * <li>Must have an empty constructor.</li>
+ * <li>Class should be annotated with {@link ComponentDescriptor}.</li>
+ * <li>Getters for properties editable by users should be annotated with
+ * {@link EditableProperty}.</li>
+ * <li>Component configuration should be stored int <code>public static</code>
+ * fields so they can be set through config file.</li>
+ * </ul>
+ * 
+ * @author Branislav Stojkovic
+ * 
+ * @param <T>
+ *            type of component values, e.g. Resistance for resistors or String
+ *            for transistors.
+ */
+public interface IDIYComponent<T> extends Serializable {
+
+	public static final int CHASSIS = 1;
+	public static final int BOARD = 2;
+	public static final int TRACE = 3;
+	public static final int COMPONENT = 4;
+	public static final int TEXT = 5;
+
+	/**
+	 * @return component instance name.
+	 */
+	String getName();
+
+	/**
+	 * Updates component instance name.
+	 * 
+	 * @param name
+	 */
+	void setName(String name);
+
+	/**
+	 * @return component value.
+	 */
+	T getValue();
+
+	/**
+	 * Updates component value.
+	 * 
+	 * @param value
+	 */
+	void setValue(T value);
+
+	/**
+	 * @return number of control points for this component instance. May vary
+	 *         between two instances of the same type, e.g. DIL IC with 8 and 16
+	 *         pins will have 8 or 16 pins although they are of the same type.
+	 */
+	int getControlPointCount();
+
+	/**
+	 * @param index
+	 * @return control point at the specified index.
+	 */
+	Point getControlPoint(int index);
+
+	/**
+	 * Updates the control point at the specified index.
+	 * 
+	 * @param point
+	 * @param index
+	 */
+	void setControlPoint(Point point, int index);
+
+	/**
+	 * @param index
+	 * @return true, if the specified control point may stick to control points
+	 *         of other components.
+	 */
+	boolean isControlPointSticky(int index);
+
+	/**
+	 * @param index
+	 * @return true, if the specified control point may overlap with other
+	 *         control points <b>of the same component</b>. The other control
+	 *         point must be able to overlap too.
+	 */
+	boolean canControlPointOverlap(int index);
+
+	VisibilityPolicy getControlPointVisibilityPolicy(int index);
+
+	/**
+	 * Draws the component onto the {@link Graphics2D}.
+	 * 
+	 * @param g2d
+	 * @param componentState
+	 * @param outlineMode
+	 * @param project
+	 * @param drawingObserver
+	 */
+	void draw(Graphics2D g2d, ComponentState componentState, boolean outlineMode, Project project,
+			IDrawingObserver drawingObserver);
+
+	/**
+	 * Draws icon representation of the component. This should not depend on
+	 * component state, i.e. it should be treated as a static method.
+	 * 
+	 * @param g2d
+	 * @param width
+	 * @param height
+	 */
+	void drawIcon(Graphics2D g2d, int width, int height);
+}

src/org/diylc/core/IDrawingObserver.java

@@ -0,0 +1,15 @@
+package org.diylc.core;
+
+/**
+ * Interface for tracking component drawing process. Components may use it to
+ * stop or restart tracking. Anything drawn while tracking is stopped will not
+ * be added to the mouse hot-spot area.
+ * 
+ * @author Branislav Stojkovic
+ */
+public interface IDrawingObserver {
+
+	void stopTracking();
+
+	void startTracking();
+}

src/org/diylc/core/IPropertyValidator.java

@@ -0,0 +1,16 @@
+package org.diylc.core;
+
+/**
+ * Interface for validating property value changes.
+ * 
+ * @author Branislav Stojkovic
+ */
+public interface IPropertyValidator {
+
+	/**
+	 * @param value
+	 * @throws ValidationException
+	 *             if validation fails. Message will contain the reason.
+	 */
+	void validate(Object value) throws ValidationException;
+}

src/org/diylc/core/IView.java

@@ -0,0 +1,38 @@
+package org.diylc.core;
+
+import java.util.List;
+import java.util.Set;
+
+import org.diylc.common.PropertyWrapper;
+
+
+/**
+ * Base interface for the main GUI component.
+ * 
+ * @author Branislav Stojkovic
+ */
+public interface IView {
+
+	public static final int ERROR_MESSAGE = 0;
+	public static final int INFORMATION_MESSAGE = 1;
+	public static final int WARNING_MESSAGE = 2;
+	public static final int QUESTION_MESSAGE = 3;
+	public static final int PLAIN_MESSAGE = -1;
+	public static final int DEFAULT_OPTION = -1;
+	public static final int YES_NO_OPTION = 0;
+	public static final int YES_NO_CANCEL_OPTION = 1;
+	public static final int OK_CANCEL_OPTION = 2;
+	public static final int YES_OPTION = 0;
+	public static final int NO_OPTION = 1;
+	public static final int CANCEL_OPTION = 2;
+	public static final int OK_OPTION = 0;
+	
+	public static final String CHECK_BOX_MENU_ITEM = "org.diylc.checkBoxMenuItem";
+	public static final String RADIO_BUTTON_GROUP_KEY = "org.diylc.radioButtonGroup";
+
+	void showMessage(String message, String title, int messageType);
+
+	int showConfirmDialog(String message, String title, int optionType, int messageType);
+	
+	boolean editProperties(List<PropertyWrapper> properties, Set<PropertyWrapper> defaultedProperties);
+}

src/org/diylc/core/Project.java

@@ -0,0 +1,225 @@
+package org.diylc.core;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+import org.diylc.core.annotations.EditableProperty;
+import org.diylc.core.annotations.PositiveMeasureValidator;
+import org.diylc.core.measures.Size;
+import org.diylc.core.measures.SizeUnit;
+
+import com.diyfever.gui.update.VersionNumber;
+
+/**
+ * Entity class that defines a project. Contains project properties and a
+ * collection of components.This class is serialized to file. Some filed getters
+ * are tagged with {@link EditableProperty} to enable for user to edit them.
+ * 
+ * @author Branislav Stojkovic
+ */
+public class Project implements Serializable {
+
+	private static final long serialVersionUID = 1L;
+
+	public static String DEFAULT_TITLE = "New Project";
+	public static Size DEFAULT_WIDTH = new Size(29d, SizeUnit.cm);
+	public static Size DEFAULT_HEIGHT = new Size(21d, SizeUnit.cm);
+	public static Size DEFAULT_GRID_SPACING = new Size(0.1d, SizeUnit.in);
+
+	private VersionNumber fileVersion;
+	
+	private String title;
+	private String author;
+	private String description;
+	private Size width;
+	private Size height;
+	private Size gridSpacing;
+	private List<IDIYComponent<?>> components;
+	private Set<Set<IDIYComponent<?>>> groups;
+	private Set<Integer> lockedLayers;
+
+	public Project() {
+		components = new ArrayList<IDIYComponent<?>>();
+		groups = new HashSet<Set<IDIYComponent<?>>>();
+		lockedLayers = new HashSet<Integer>();
+		title = DEFAULT_TITLE;
+		author = System.getProperty("user.name");
+		width = DEFAULT_WIDTH;
+		height = DEFAULT_HEIGHT;
+		gridSpacing = DEFAULT_GRID_SPACING;
+	}
+
+	@EditableProperty(defaultable = false)
+	public String getTitle() {
+		return title;
+	}
+
+	public void setTitle(String title) {
+		this.title = title;
+	}
+
+	@EditableProperty
+	public String getAuthor() {
+		return author;
+	}
+
+	public void setAuthor(String author) {
+		this.author = author;
+	}
+
+	@EditableProperty(defaultable = false)
+	public String getDescription() {
+		return description;
+	}
+
+	public void setDescription(String description) {
+		this.description = description;
+	}
+
+	@EditableProperty
+	public Size getWidth() {
+		return width;
+	}
+
+	public void setWidth(Size width) {
+		this.width = width;
+	}
+
+	@EditableProperty
+	public Size getHeight() {
+		return height;
+	}
+
+	public void setHeight(Size height) {
+		this.height = height;
+	}
+
+	@EditableProperty(name = "Grid spacing", validatorClass = SpacingValidator.class)
+	public Size getGridSpacing() {
+		return gridSpacing;
+	}
+
+	public void setGridSpacing(Size gridSpacing) {
+		this.gridSpacing = gridSpacing;
+	}
+
+	/**
+	 * List of components sorted by z-order ascending.
+	 * 
+	 * @return
+	 */
+	public List<IDIYComponent<?>> getComponents() {
+		return components;
+	}
+
+	/**
+	 * Set of grouped components.
+	 * 
+	 * @return
+	 */
+	public Set<Set<IDIYComponent<?>>> getGroups() {
+		return groups;
+	}
+
+	public Set<Integer> getLockedLayers() {
+		return lockedLayers;
+	}
+	
+	public VersionNumber getFileVersion() {
+		return fileVersion;
+	}
+	
+	public void setFileVersion(VersionNumber fileVersion) {
+		this.fileVersion = fileVersion;
+	}
+
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + ((author == null) ? 0 : author.hashCode());
+		result = prime * result + ((components == null) ? 0 : components.hashCode());
+		result = prime * result + ((description == null) ? 0 : description.hashCode());
+		result = prime * result + ((height == null) ? 0 : height.hashCode());
+		result = prime * result + ((title == null) ? 0 : title.hashCode());
+		result = prime * result + ((width == null) ? 0 : width.hashCode());
+		return result;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj)
+			return true;
+		if (obj == null)
+			return false;
+		if (getClass() != obj.getClass())
+			return false;
+		Project other = (Project) obj;
+		if (author == null) {
+			if (other.author != null)
+				return false;
+		} else if (!author.equals(other.author))
+			return false;
+		if (components == null) {
+			if (other.components != null)
+				return false;
+		} else if (!components.equals(other.components))
+			return false;
+		if (description == null) {
+			if (other.description != null)
+				return false;
+		} else if (!description.equals(other.description))
+			return false;
+		if (height == null) {
+			if (other.height != null)
+				return false;
+		} else if (!height.equals(other.height))
+			return false;
+		if (title == null) {
+			if (other.title != null)
+				return false;
+		} else if (!title.equals(other.title))
+			return false;
+		if (width == null) {
+			if (other.width != null)
+				return false;
+		} else if (!width.equals(other.width))
+			return false;
+		return true;
+	}
+
+	@Override
+	public String toString() {
+		return title;
+	}
+
+	public static class SpacingValidator extends PositiveMeasureValidator {
+
+		@Override
+		public void validate(Object value) throws ValidationException {
+			super.validate(value);
+			Size size = (Size) value;
+			if (size.compareTo(new Size(1d, SizeUnit.mm)) < 0) {
+				throw new ValidationException("must be greater than 1mm");
+			}
+			if (size.compareTo(new Size(1d, SizeUnit.in)) > 0) {
+				throw new ValidationException("must be less than 1in");
+			}
+		}
+	}
+
+	// @Override
+	// public Project clone() throws CloneNotSupportedException {
+	// List<IDIYComponent> clonedComponents = new
+	// ArrayList<IDIYComponent>();
+	// for (IDIYComponent component : components) {
+	// clonedComponents.add(component.clone());
+	// }
+	// Project project = new Project(title, author, description,
+	// width.clone(), height.clone(), clonedComponents);
+	// return project;
+	// }
+}

src/org/diylc/core/Theme.java

@@ -0,0 +1,86 @@
+package org.diylc.core;
+
+import java.awt.Color;
+import java.io.Serializable;
+
+public class Theme implements Serializable {
+
+	private static final long serialVersionUID = 1L;
+
+	private String name;
+	private Color bgColor;
+	private Color gridColor;
+	private Color outlineColor;
+
+	public Theme(String name, Color bgColor, Color gridColor, Color outlineColor) {
+		super();
+		this.name = name;
+		this.bgColor = bgColor;
+		this.gridColor = gridColor;
+		this.outlineColor = outlineColor;
+	}
+
+	public String getName() {
+		return name;
+	}
+
+	public Color getBgColor() {
+		return bgColor;
+	}
+
+	public Color getGridColor() {
+		return gridColor;
+	}
+
+	public Color getOutlineColor() {
+		return outlineColor;
+	}
+
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + ((bgColor == null) ? 0 : bgColor.hashCode());
+		result = prime * result + ((gridColor == null) ? 0 : gridColor.hashCode());
+		result = prime * result + ((outlineColor == null) ? 0 : outlineColor.hashCode());
+		result = prime * result + ((name == null) ? 0 : name.hashCode());
+		return result;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj)
+			return true;
+		if (obj == null)
+			return false;
+		if (getClass() != obj.getClass())
+			return false;
+		Theme other = (Theme) obj;
+		if (bgColor == null) {
+			if (other.bgColor != null)
+				return false;
+		} else if (!bgColor.equals(other.bgColor))
+			return false;
+		if (gridColor == null) {
+			if (other.gridColor != null)
+				return false;
+		} else if (!gridColor.equals(other.gridColor))
+			return false;
+		if (outlineColor == null) {
+			if (other.outlineColor != null)
+				return false;
+		} else if (!outlineColor.equals(other.outlineColor))
+			return false;
+		if (name == null) {
+			if (other.name != null)
+				return false;
+		} else if (!name.equals(other.name))
+			return false;
+		return true;
+	}
+
+	@Override
+	public String toString() {
+		return name;
+	}
+}

src/org/diylc/core/ValidationException.java

@@ -0,0 +1,11 @@
+
+package org.diylc.core;
+
+public class ValidationException extends Exception {
+
+	private static final long serialVersionUID = 1L;
+
+	public ValidationException(String message) {
+		super(message);
+	}
+}

src/org/diylc/core/VisibilityPolicy.java

@@ -0,0 +1,22 @@
+package org.diylc.core;
+
+/**
+ * Enumerates control point visibility policies.
+ * 
+ * @author Branislav Stojkovic
+ */
+public enum VisibilityPolicy {
+
+	/**
+	 * Control point should be rendered all the time.
+	 */
+	ALWAYS,
+	/**
+	 * Control point should be rendered only when the component is selected.
+	 */
+	WHEN_SELECTED,
+	/**
+	 * Control point should not be rendered regardless of component selection.
+	 */
+	NEVER;
+}

src/org/diylc/core/annotations/ComponentDescriptor.java

@@ -0,0 +1,62 @@
+package org.diylc.core.annotations;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+import org.diylc.core.CreationMethod;
+import org.diylc.core.IDIYComponent;
+
+/**
+ * Annotation for {@link IDIYComponent} implementation. Describes component
+ * properties.
+ * 
+ * @author Branislav Stojkovic
+ */
+@Retention(RetentionPolicy.RUNTIME)
+public @interface ComponentDescriptor {
+
+	/**
+	 * @return component type name.
+	 */
+	String name();
+
+	/**
+	 * @return component type description.
+	 */
+	String description();
+
+	/**
+	 * @return method that should be used to create a component. If
+	 *         <code>CreationMethod.POINT_BY_POINT</code> is used, user will
+	 *         have to select ending points before the component is created.
+	 */
+	CreationMethod creationMethod() default CreationMethod.SINGLE_CLICK;
+
+	/**
+	 * @return component category, e.g. "Passive", "Semiconductors", etc.
+	 */
+	String category();
+
+	/**
+	 * @return component author name.
+	 */
+	String author();
+
+	/**
+	 * @return prefix that will be used to generate component instance names,
+	 *         e.g. "R" for resistors or "Q" for transistors.
+	 */
+	String instanceNamePrefix();
+
+	/**
+	 * @return Z-order of the component.
+	 */
+	double zOrder();
+
+	/**
+	 * @return when false, moving one control point will cause all the others to
+	 *         move together with it.
+	 */
+	boolean stretchable() default true;
+
+}

src/org/diylc/core/annotations/EditableProperty.java

@@ -0,0 +1,42 @@
+package org.diylc.core.annotations;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+import org.diylc.core.AllowAllValidator;
+import org.diylc.core.IPropertyValidator;
+
+/**
+ * Used to annotate editable component property. Editable property XYZ must have
+ * both getter and setter named <code>getXYZ</code> and <code>setXYZ</code>
+ * respectively and this annotation must be placed on the getter method.
+ * 
+ * @author Branislav Stojkovic
+ */
+@Retention(RetentionPolicy.RUNTIME)
+public @interface EditableProperty {
+
+	/**
+	 * Returns property name. If left blank property name will be extracted from
+	 * the getter name, e.g. getter <code>getXYZ</code> will induce property
+	 * name <code>XYZ</code>. <br>
+	 * Default value is blank.
+	 * 
+	 * @return
+	 */
+	String name() default "";
+
+	/**
+	 * If true, application may set default value for this property. <br>
+	 * Default value is true.
+	 * 
+	 * @return
+	 */
+	boolean defaultable() default true;
+	
+	/**
+	 * Class of validator to use to 
+	 * @return
+	 */
+	Class<? extends IPropertyValidator> validatorClass() default AllowAllValidator.class;
+}

src/org/diylc/core/annotations/PositiveMeasureValidator.java

@@ -0,0 +1,20 @@
+package org.diylc.core.annotations;
+
+import org.diylc.core.IPropertyValidator;
+import org.diylc.core.ValidationException;
+import org.diylc.core.measures.AbstractMeasure;
+
+public class PositiveMeasureValidator implements IPropertyValidator {
+
+	@Override
+	public void validate(Object value) throws ValidationException {
+		if (value instanceof AbstractMeasure) {
+			AbstractMeasure measure = (AbstractMeasure) value;
+			if (measure.getValue() < 0) {
+				throw new ValidationException("must be greater than zero.");
+			}
+		} else {
+			throw new ValidationException("wrong data type, measure expected.");
+		}
+	}
+}

src/org/diylc/core/measures/AbstractMeasure.java

@@ -0,0 +1,81 @@
+package org.diylc.core.measures;
+
+import java.io.Serializable;
+import java.text.DecimalFormat;
+import java.text.Format;
+
+public class AbstractMeasure<T extends Enum<? extends Unit>> implements Serializable, Cloneable {
+
+	private static final long serialVersionUID = 1L;
+
+	protected static final Format format = new DecimalFormat("0.####");
+
+	protected Double value;
+	protected T unit;
+
+	public AbstractMeasure() {
+	}
+
+	public AbstractMeasure(Double value, T unit) {
+		super();
+		this.value = value;
+		this.unit = unit;
+	}
+
+	public Double getValue() {
+		return value;
+	}
+
+	public void setValue(Double value) {
+		this.value = value;
+	}
+
+	public T getUnit() {
+		return unit;
+	}
+
+	public void setUnit(T multiplier) {
+		this.unit = multiplier;
+	}
+	
+	@Override
+	public Object clone() throws CloneNotSupportedException {
+		return super.clone();
+	}
+
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + ((unit == null) ? 0 : unit.hashCode());
+		result = prime * result + ((value == null) ? 0 : value.hashCode());
+		return result;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj)
+			return true;
+		if (obj == null)
+			return false;
+		if (getClass() != obj.getClass())
+			return false;
+		AbstractMeasure<?> other = (AbstractMeasure<?>) obj;
+		if (unit == null) {
+			if (other.unit != null)
+				return false;
+		} else if (!unit.equals(other.unit))
+			return false;
+		if (value == null) {
+			if (other.value != null)
+				return false;
+		} else if (!value.equals(other.value))
+			return false;
+		return true;
+	}
+
+	@Override
+	public String toString() {
+		return format.format(value) + " " + unit;
+	}
+}

src/org/diylc/core/measures/Capacitance.java

@@ -0,0 +1,31 @@
+package org.diylc.core.measures;
+
+public class Capacitance extends AbstractMeasure<CapacitanceUnit> {
+
+	private static final long serialVersionUID = 1L;
+
+	public Capacitance() {
+		super();
+		// TODO Auto-generated constructor stub
+	}
+
+	public Capacitance(Double value, CapacitanceUnit unit) {
+		super(value, unit);
+		// TODO Auto-generated constructor stub
+	}
+
+	@Override
+	public Capacitance clone() throws CloneNotSupportedException {
+		return new Capacitance(value, unit);
+	}
+	
+	public static Capacitance parseCapacitance(String value) {
+		for (CapacitanceUnit unit : CapacitanceUnit.values()) {
+			if (value.toLowerCase().endsWith(unit.toString().toLowerCase())) {
+				value = value.substring(0, value.length() - unit.toString().length() - 1).trim();
+				return new Capacitance(Double.parseDouble(value), unit);
+			}
+		}
+		throw new IllegalArgumentException("Could not parse capacitance: " + value);
+	}
+}

src/org/diylc/core/measures/CapacitanceUnit.java

@@ -0,0 +1,24 @@
+package org.diylc.core.measures;
+
+public enum CapacitanceUnit implements Unit {
+
+	pF(1, "pF"), nF(1e3, "nF"), uF(1e6, "uF"), mF(1e9, "mF"), F(1e12, "F");
+
+	double factor;
+	String display;
+
+	private CapacitanceUnit(double factor, String display) {
+		this.factor = factor;
+		this.display = display;
+	}
+
+	@Override
+	public double getFactor() {
+		return factor;
+	}
+
+	@Override
+	public String toString() {
+		return display;
+	}
+}

src/org/diylc/core/measures/Inductance.java

@@ -0,0 +1,31 @@
+package org.diylc.core.measures;
+
+public class Inductance extends AbstractMeasure<InductanceUnit> {
+
+	private static final long serialVersionUID = 1L;
+
+	public Inductance() {
+		super();
+		// TODO Auto-generated constructor stub
+	}
+
+	public Inductance(Double value, InductanceUnit unit) {
+		super(value, unit);
+		// TODO Auto-generated constructor stub
+	}
+
+	@Override
+	public Inductance clone() throws CloneNotSupportedException {
+		return new Inductance(value, unit);
+	}
+
+	public static Inductance parseCapacitance(String value) {
+		for (InductanceUnit unit : InductanceUnit.values()) {
+			if (value.toLowerCase().endsWith(unit.toString().toLowerCase())) {
+				value = value.substring(0, value.length() - unit.toString().length() - 1).trim();
+				return new Inductance(Double.parseDouble(value), unit);
+			}
+		}
+		throw new IllegalArgumentException("Could not parse inductance: " + value);
+	}
+}

src/org/diylc/core/measures/InductanceUnit.java

@@ -0,0 +1,24 @@
+package org.diylc.core.measures;
+
+public enum InductanceUnit implements Unit {
+
+	pH(1, "pH"), nH(1e3, "nH"), uH(1e6, "\u03bcH"), mH(1e9, "mH"), H(1e12, "H");
+
+	double factor;
+	String display;
+
+	private InductanceUnit(double factor, String display) {
+		this.factor = factor;
+		this.display = display;
+	}
+
+	@Override
+	public double getFactor() {
+		return factor;
+	}
+
+	@Override
+	public String toString() {
+		return display;
+	}
+}

src/org/diylc/core/measures/Resistance.java

@@ -0,0 +1,78 @@
+package org.diylc.core.measures;
+
+import java.awt.Color;
+
+import org.diylc.common.ResistorColorCode;
+
+public class Resistance extends AbstractMeasure<ResistanceUnit> {
+
+	private static final long serialVersionUID = 1L;
+
+	private static final Color[] COLOR_DIGITS = new Color[] { Color.black, Color.decode("#8B4513"),
+			Color.red, Color.orange, Color.yellow, Color.decode("#76EE00"), Color.blue,
+			Color.decode("#91219E"), Color.lightGray, Color.white };
+	private static final Color[] COLOR_MULTIPLIER = new Color[] { Color.lightGray.brighter(),
+			Color.decode("#FFB90F"), Color.black, Color.decode("#8B4513"), Color.red, Color.orange,
+			Color.yellow, Color.decode("#76EE00"), Color.blue };
+
+	public Resistance() {
+		super();
+		// TODO Auto-generated constructor stub
+	}
+
+	public Resistance(Double value, ResistanceUnit multiplier) {
+		super(value, multiplier);
+		// TODO Auto-generated constructor stub
+	}
+
+	@Override
+	public Resistance clone() throws CloneNotSupportedException {
+		return new Resistance(value, unit);
+	}
+
+	public Color[] getColorCode(ResistorColorCode resistorColorCode) {
+		Color[] bands;
+		double base = getValue() * getUnit().getFactor();
+		int multiplier = 0;
+		while (base > (resistorColorCode == ResistorColorCode._4_BAND ? 99 : 999)) {
+			multiplier += 1;
+			base /= 10;
+		}
+		while (base < (resistorColorCode == ResistorColorCode._4_BAND ? 10 : 100)) {
+			multiplier -= 1;
+			base *= 10;
+		}
+		if (multiplier > 6 || multiplier < -2) {
+			// Out of range.
+			return new Color[] {};
+		}
+		switch (resistorColorCode) {
+		case _4_BAND:
+			bands = new Color[3];
+			bands[0] = COLOR_DIGITS[(int) (base / 10)];
+			bands[1] = COLOR_DIGITS[(int) (base % 10)];
+			bands[2] = COLOR_MULTIPLIER[multiplier + 2];
+			break;
+		case _5_BAND:
+			bands = new Color[4];
+			bands[0] = COLOR_DIGITS[(int) (base / 100)];
+			bands[1] = COLOR_DIGITS[(int) (base / 10 % 10)];
+			bands[2] = COLOR_DIGITS[(int) (base % 10)];
+			bands[3] = COLOR_MULTIPLIER[multiplier + 2];
+			break;
+		default:
+			bands = new Color[] {};
+		}
+		return bands;
+	}
+
+	public static Resistance parseResistance(String value) {
+		for (ResistanceUnit unit : ResistanceUnit.values()) {
+			if (value.toLowerCase().endsWith(unit.toString().toLowerCase())) {
+				value = value.substring(0, value.length() - unit.toString().length() - 1).trim();
+				return new Resistance(Double.parseDouble(value), unit);
+			}
+		}
+		throw new IllegalArgumentException("Could not parse resistance: " + value);
+	}
+}

src/org/diylc/core/measures/ResistanceUnit.java

@@ -0,0 +1,24 @@
+package org.diylc.core.measures;
+
+public enum ResistanceUnit implements Unit {
+
+	R(1, "\u03a9"), K(1e3, "K"), M(1e6, "M");
+
+	double factor;
+	String display;
+
+	private ResistanceUnit(double factor, String display) {
+		this.factor = factor;
+		this.display = display;
+	}
+
+	@Override
+	public double getFactor() {
+		return factor;
+	}
+
+	@Override
+	public String toString() {
+		return display;
+	}
+}

src/org/diylc/core/measures/Size.java

@@ -0,0 +1,47 @@
+package org.diylc.core.measures;
+
+import org.diylc.utils.Constants;
+
+public class Size extends AbstractMeasure<SizeUnit> implements Comparable<Size> {
+
+	private static final long serialVersionUID = 1L;
+
+	public Size() {
+		super();
+		// TODO Auto-generated constructor stub
+	}
+
+	public Size(Double value, SizeUnit unit) {
+		super(value, unit);
+		// TODO Auto-generated constructor stub
+	}
+
+	public double convertToPixels() {
+//		double factor = getUnit().getFactor() / SizeUnit.in.getFactor();
+//		int grids = (int) (factor * getValue() * Constants.GRIDS_PER_INCH);
+//		double remainder = (factor * getValue() * Constants.GRIDS_PER_INCH) - grids;
+//		return (int) Math.round(Constants.PIXELS_PER_INCH / Constants.GRIDS_PER_INCH
+//				* (grids + remainder));
+		return getValue() * getUnit().getFactor() / SizeUnit.in.getFactor() * Constants.PIXELS_PER_INCH;
+	}
+
+	@Override
+	public Size clone() throws CloneNotSupportedException {
+		return new Size(value, unit);
+	}
+	
+	public static Size parseSize(String value) {
+		for (SizeUnit unit : SizeUnit.values()) {
+			if (value.toLowerCase().endsWith(unit.toString().toLowerCase())) {
+				value = value.substring(0, value.length() - unit.toString().length() - 1).trim();
+				return new Size(Double.parseDouble(value), unit);
+			}
+		}
+		throw new IllegalArgumentException("Could not parse size: " + value);
+	}
+
+	@Override
+	public int compareTo(Size o) {
+		return new Double(value * unit.getFactor()).compareTo(o.getValue() * o.getUnit().getFactor());
+	}
+}

src/org/diylc/core/measures/SizeUnit.java

@@ -0,0 +1,17 @@
+package org.diylc.core.measures;
+
+public enum SizeUnit implements Unit {
+
+	mm(1d), cm(10d), m(1e4d), in(25.4d), ft(25.4d * 12), yd(9144d);
+
+	double factor;
+
+	private SizeUnit(double factor) {
+		this.factor = factor;
+	}
+
+	@Override
+	public double getFactor() {
+		return factor;
+	}
+}

src/org/diylc/core/measures/Unit.java

@@ -0,0 +1,6 @@
+package org.diylc.core.measures;
+
+public interface Unit {
+
+	double getFactor();
+}