Adds some additional functionality for getting and finding element/relationship styles.

Author: simonbrowndotje

docs/changelog.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## 1.15.1 (23rd September 2022)
+
+- Adds some additional functionality for getting and finding element/relationship styles.
+
 ## 1.15.0 (13th September 2022)
 
 - Adds documentation section filenames into the model.

structurizr-core/src/com/structurizr/view/Styles.java

@@ -83,6 +83,20 @@ public RelationshipStyle addRelationshipStyle(String tag) {
         return relationshipStyle;
     }
 
+    /**
+     * Gets the element style that has been defined (in this workspace) for the given tag.
+     *
+     * @param tag   the tag (a String)
+     * @return      an ElementStyle instance, or null if no element style has been defined in this workspace
+     */
+    public ElementStyle getElementStyle(String tag) {
+        if (StringUtils.isNullOrEmpty(tag)) {
+            throw new IllegalArgumentException("A tag must be specified.");
+        }
+
+        return elements.stream().filter(es -> es.getTag().equals(tag)).findFirst().orElse(null);
+    }
+
     /**
      * Finds the element style for the given tag. This method creates an empty style,
      * and copies properties from any element styles (from the workspace and any themes) for the given tag.
@@ -120,6 +134,20 @@ public ElementStyle findElementStyle(String tag) {
         }
     }
 
+    /**
+     * Gets the relationship style that has been defined (in this workspace) for the given tag.
+     *
+     * @param tag   the tag (a String)
+     * @return      an RelationshipStyle instance, or null if no relationship style has been defined in this workspace
+     */
+    public RelationshipStyle getRelationshipStyle(String tag) {
+        if (StringUtils.isNullOrEmpty(tag)) {
+            throw new IllegalArgumentException("A tag must be specified.");
+        }
+
+        return relationships.stream().filter(rs -> rs.getTag().equals(tag)).findFirst().orElse(null);
+    }
+
     /**
      * Finds the relationship style for the given tag. This method creates an empty style,
      * and copies properties from any relationship styles (from the workspace and any themes) for the given tag.

structurizr-core/test/unit/com/structurizr/view/StylesTests.java

@@ -333,4 +333,66 @@ void clearRelationshipStyles_RemovesAllRelationshipStyles() {
         assertEquals(0, styles.getRelationships().size());
     }
 
+    @Test
+    void getElementStyle_ThrowsAnException_WhenGivenNoTag() {
+        try {
+            styles.getElementStyle(null);
+            fail();
+        } catch (IllegalArgumentException iae) {
+            assertEquals("A tag must be specified.", iae.getMessage());
+        }
+
+        try {
+            styles.getElementStyle(" ");
+            fail();
+        } catch (IllegalArgumentException iae) {
+            assertEquals("A tag must be specified.", iae.getMessage());
+        }
+    }
+
+    @Test
+    void getElementStyle_ReturnsNull_WhenThereIsNoStyleForTheGivenTag() {
+        ElementStyle style = styles.getElementStyle("Tag");
+        assertNull(style);
+    }
+
+    @Test
+    void getElementStyle_ReturnsTheElementStyle_WhenThereIsAStyleForTheGivenTag() {
+        styles.addElementStyle("Tag").background("#ffffff");
+
+        ElementStyle style = styles.getElementStyle("Tag");
+        assertEquals("#ffffff", style.getBackground());
+    }
+
+    @Test
+    void getRelationshipStyle_ThrowsAnException_WhenGivenNoTag() {
+        try {
+            styles.getRelationshipStyle(null);
+            fail();
+        } catch (IllegalArgumentException iae) {
+            assertEquals("A tag must be specified.", iae.getMessage());
+        }
+
+        try {
+            styles.getRelationshipStyle(" ");
+            fail();
+        } catch (IllegalArgumentException iae) {
+            assertEquals("A tag must be specified.", iae.getMessage());
+        }
+    }
+
+    @Test
+    void getRelationshipStyle_ReturnsNull_WhenThereIsNoStyleForTheGivenTag() {
+        RelationshipStyle style = styles.getRelationshipStyle("Tag");
+        assertNull(style);
+    }
+
+    @Test
+    void getRelationshipStyle_ReturnsTheRelationshipStyle_WhenThereIsAStyleForTheGivenTag() {
+        styles.addRelationshipStyle("Tag").color("#ffffff");
+
+        RelationshipStyle style = styles.getRelationshipStyle("Tag");
+        assertEquals("#ffffff", style.getColor());
+    }
+
 }