Bug 433269 - TextBuilder: helper class for constructing TextStyleRegions

Change-Id: I78aea5cd1d15fdbbd6c2650963f274d493486ea8

1 files changed, 314 insertions, 0 deletions

diff --git a/plugins/org.eclipse.graphiti/src/org/eclipse/graphiti/util/TextBuilder.java b/plugins/org.eclipse.graphiti/src/org/eclipse/graphiti/util/TextBuilder.java
new file mode 100644
index 00000000..698c7c62
--- /dev/null
+++ b/plugins/org.eclipse.graphiti/src/org/eclipse/graphiti/util/TextBuilder.java
@@ -0,0 +1,314 @@
+/*******************************************************************************
+ * <copyright>
+ *
+ * Copyright (c) 2014, 2014 SAP AG.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Eindhoven University of Technology (Albert Hofkamp) - Bug 440796 - initial API, implementation and documentation
+ *
+ * </copyright>
+ *
+ *******************************************************************************/
+package org.eclipse.graphiti.util;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.eclipse.graphiti.mm.algorithms.styles.Color;
+import org.eclipse.graphiti.mm.algorithms.styles.Font;
+import org.eclipse.graphiti.mm.algorithms.styles.StylesFactory;
+import org.eclipse.graphiti.mm.algorithms.styles.TextStyle;
+import org.eclipse.graphiti.mm.algorithms.styles.TextStyleRegion;
+import org.eclipse.graphiti.mm.algorithms.styles.UnderlineStyle;
+
+/**
+ * Class to construct {@link TextStyleRegion}s while adding text.
+ * 
+ * @since 0.12
+ */
+public class TextBuilder {
+
+	/** Constructed text string. */
+	private StringBuilder text = new StringBuilder();
+
+	/** Number of code points in {@link #text}. */
+	private int length = 0;
+
+	/** Regions created in the collected text. */
+	private List<TextStyleRegion> regions = new ArrayList<TextStyleRegion>();
+
+	/** Partly finished text styles. */
+	private Map<String, TextBuilderRegion> styles = new LinkedHashMap<String, TextBuilderRegion>();
+
+	/**
+	 * Add text to the builder.
+	 * 
+	 * @param text
+	 *            Text to append.
+	 */
+	public void add(String text) {
+		length += text.length();
+		this.text.append(text);
+	}
+
+	/**
+	 * Get current length of the collected text.
+	 * 
+	 * @return Length of the text collected so far (number of code points).
+	 */
+	public int getLength() {
+		return length;
+	}
+
+	/**
+	 * Is any text added yet?
+	 * 
+	 * @return {@code true} if no text added yet, else {@code false}.
+	 */
+	public boolean isEmpty() {
+		return length == 0;
+	}
+
+	/**
+	 * Get the collected text.
+	 * 
+	 * @return The concatenated strings previously given through {@link #add}.
+	 */
+	@Override
+	public String toString() {
+		return text.toString();
+	}
+
+	/**
+	 * Get the regions created and finished for the text.
+	 * 
+	 * @return Regions of the text.
+	 */
+	public List<TextStyleRegion> getRegions() {
+		return regions;
+	}
+
+	/**
+	 * Start a new region in the text. Returns the created region for setting
+	 * the style of the new region.
+	 * 
+	 * @param name
+	 *            Name of the region.
+	 * @return The created region.
+	 */
+	public TextBuilderRegion startRegion(String name) {
+		TextBuilderRegion tbr = new TextBuilderRegion().setStart(length);
+		styles.put(name, tbr);
+		return tbr;
+	}
+
+	/**
+	 * Get a previously created and not yet finished region.
+	 * 
+	 * @param name
+	 *            Name of the region to retrieve.
+	 * @return The queried region if it exists, else {@code null}.
+	 */
+	public TextBuilderRegion getRegion(String name) {
+		return styles.get(name);
+	}
+
+	/**
+	 * Finish a region.
+	 * 
+	 * @param name
+	 *            Name of the region to finish.
+	 */
+	public void finishRegion(String name) {
+		TextBuilderRegion region = styles.get(name);
+		styles.remove(name);
+
+		if (region != null && region.getStyle() != null) {
+			TextStyleRegion styleRegion;
+			styleRegion = StylesFactory.eINSTANCE.createTextStyleRegion();
+			styleRegion.setStart(region.getStart());
+			styleRegion.setStyle(region.getStyle());
+			styleRegion.setEnd(length);
+			regions.add(styleRegion);
+		}
+	}
+
+	/**
+	 * Drop a region that was created but not yet finished.
+	 * 
+	 * @param name
+	 *            Name of the region to forget.
+	 */
+	public void forgetRegion(String name) {
+		styles.remove(name);
+	}
+
+	/**
+	 * Inner class for storing the partial region styles.
+	 */
+	public static class TextBuilderRegion {
+		/** Current style of the region, {@code null} means default style. */
+		private TextStyle style = null;
+
+		/** Start offset of the region in the text. */
+		private int start = 0;
+
+		/** Constructor of the {@link TextBuilderRegion} class. */
+		public TextBuilderRegion() {
+			style = null;
+		}
+
+		/**
+		 * Get start offset of the region in the text.
+		 * 
+		 * @return The start offset of the region.
+		 */
+		public int getStart() {
+			return start;
+		}
+
+		/**
+		 * Get the text style of the region in the text.
+		 * 
+		 * @return The text style, or {@code null} for the default style.
+		 */
+		public TextStyle getStyle() {
+			return style;
+		}
+
+		/** Ensure a non-default style is available for modification. */
+		private void ensureStyle() {
+			if (style == null)
+				style = StylesFactory.eINSTANCE.createTextStyle();
+		}
+
+		/**
+		 * Assign a style to the region of text.
+		 * 
+		 * @param style
+		 *            Style to assign.
+		 * @return The updated partial region style.
+		 */
+		public TextBuilderRegion setStyle(TextStyle style) {
+			this.style = style;
+			return this;
+		}
+
+		/**
+		 * Assign a start to the partial region style.
+		 * 
+		 * @param start
+		 *            New start offset of the region in the text.
+		 * @return The updated partial region style.
+		 */
+		public TextBuilderRegion setStart(int start) {
+			this.start = start;
+			return this;
+		}
+
+		/**
+		 * Set the underline style for the region.
+		 * 
+		 * @param uStyle
+		 *            Underline style to assign. {@code null} means disable
+		 *            underline.
+		 * @param col
+		 *            Color of the underline, {@code null} means skip setting
+		 *            the color.
+		 * @return The updated partial region style.
+		 */
+		public TextBuilderRegion setUnderline(UnderlineStyle uStyle, Color col) {
+			ensureStyle();
+			if (uStyle == null) {
+				style.setUnderline(false);
+			} else {
+				style.setUnderline(true);
+				style.setUnderlineStyle(uStyle);
+			}
+			setUnderline(col);
+			return this;
+		}
+
+		/**
+		 * Set the underline color for the region.
+		 * 
+		 * @param col
+		 *            Color of the underline, {@code null} means skip setting
+		 *            the color.
+		 * @return The updated partial region style.
+		 */
+		public TextBuilderRegion setUnderline(Color col) {
+			ensureStyle();
+			if (col != null && style.isUnderline())
+				style.setUnderlineColor(col);
+			return this;
+		}
+
+		/**
+		 * Set strikeout for the region.
+		 * 
+		 * @param value
+		 *            Enable or disable strikeout.
+		 * @param col
+		 *            Color of the strikeout, if enabled. {@code null} means
+		 *            skip setting of the color.
+		 * @return The updated partial region style.
+		 */
+		public TextBuilderRegion setStrikeOut(boolean value, Color col) {
+			ensureStyle();
+			style.setStrikeout(value);
+			if (value && col != null)
+				style.setStrikeoutColor(col);
+			return this;
+		}
+
+		/**
+		 * Set the foreground color of the text for the region.
+		 * 
+		 * @param col
+		 *            Foreground color to set. {@code null} means skip setting
+		 *            of the color.
+		 * @return The updated partial region style.
+		 */
+		public TextBuilderRegion setForeground(Color col) {
+			ensureStyle();
+			if (col != null)
+				style.setForeground(col);
+			return this;
+		}
+
+		/**
+		 * Set the background color of the text for the region.
+		 * 
+		 * @param col
+		 *            Background color to set. {@code null} means skip setting
+		 *            of the color.
+		 * @return The updated partial region style.
+		 */
+		public TextBuilderRegion setBackground(Color col) {
+			ensureStyle();
+			if (col != null)
+				style.setBackground(col);
+			return this;
+		}
+
+		/**
+		 * Set the font for the region.
+		 * 
+		 * @param font
+		 *            Font to set.
+		 * @return The updated partial region style.
+		 */
+		public TextBuilderRegion setFont(Font font) {
+			ensureStyle();
+			style.setFont(font);
+			return this;
+		}
+	}
+}