[$49] Added ShortenedString

src/main/java/net/emustudio/emulib/runtime/helpers/Unchecked.java

@@ -24,7 +24,7 @@
  * <p>
  * This code was borrowed from:
  * <p>
- * http://stackoverflow.com/questions/19757300/java-8-lambda-streams-filter-by-method-with-exception
+ * <a href="http://stackoverflow.com/questions/19757300/java-8-lambda-streams-filter-by-method-with-exception">exceptions in lambda</a>
  */
 public class Unchecked {
 

src/main/java/net/emustudio/emulib/runtime/interaction/ShortenedString.java

@@ -0,0 +1,120 @@
+/*
+ * This file is part of emuLib.
+ *
+ * Copyright (C) 2006-2023  Peter Jakubčo
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package net.emustudio.emulib.runtime.interaction;
+
+import net.emustudio.emulib.runtime.helpers.StringUtils;
+import net.jcip.annotations.NotThreadSafe;
+
+import java.awt.*;
+import java.util.Objects;
+import java.util.function.Function;
+
+/**
+ * A shortened string from a value. A string computed from given value can be shortened to fit the component width.
+ *
+ * @param <T> type of the value
+ */
+@NotThreadSafe
+public class ShortenedString<T> {
+    private final T value;
+    private final Function<T, String> toString;
+    private int maxStringLength;
+
+    /**
+     * Creates a shortened string from a value.
+     *
+     * @param value    value
+     * @param toString function to convert the value to a string
+     */
+    public ShortenedString(T value, Function<T, String> toString) {
+        this.value = Objects.requireNonNull(value);
+        this.toString = Objects.requireNonNull(toString);
+    }
+
+    /**
+     * Derives the maximum length of the shortened string to fit the component width.
+     * <p>
+     * Should be called when the component width changes.
+     *
+     * @param component      component
+     * @param componentWidth custom component width (if it's different to Component.getWidth())
+     */
+    public void deriveMaxStringLength(Component component, int componentWidth) {
+        FontMetrics fontMetrics = component.getFontMetrics(component.getFont());
+        String fullString = getFullString();
+        int fullStringWidth = fontMetrics.stringWidth(fullString);
+
+        this.maxStringLength = fullString.length() * Math.min(componentWidth, fullStringWidth) / fullStringWidth;
+    }
+
+    /**
+     * Derives the maximum length of the shortened string to fit the component width.
+     * <p>
+     * Should be called when the component width changes.
+     *
+     * @param component component
+     */
+    public void deriveMaxStringLength(Component component) {
+        deriveMaxStringLength(component, component.getWidth());
+    }
+
+    /**
+     * Get the derived maximum length of the shortened string.
+     *
+     * @return max string length
+     */
+    public int getMaxStringLength() {
+        return maxStringLength;
+    }
+
+    /**
+     * Get the original value
+     *
+     * @return value
+     */
+    public T getValue() {
+        return value;
+    }
+
+    /**
+     * Get the shortened String.
+     * <p>
+     * A shortened string is cut off at derived max string length. It does it by selecting some string prefix and
+     * suffix, and inserts "..." in the middle.
+     *
+     * @return shortened string
+     */
+    public String getShortenedString() {
+        return StringUtils.shorten(toString.apply(value), maxStringLength);
+    }
+
+    /**
+     * Get the full string.
+     *
+     * @return full string
+     */
+    public String getFullString() {
+        return toString.apply(value);
+    }
+
+    @Override
+    public String toString() {
+        return getShortenedString();
+    }
+}