diff --git a/core/src/main/java/org/mapfish/print/processor/jasper/LegendProcessor.java b/core/src/main/java/org/mapfish/print/processor/jasper/LegendProcessor.java
index f6c17d462..8ff512b78 100644
--- a/core/src/main/java/org/mapfish/print/processor/jasper/LegendProcessor.java
+++ b/core/src/main/java/org/mapfish/print/processor/jasper/LegendProcessor.java
@@ -2,6 +2,7 @@
 
 import com.codahale.metrics.MetricRegistry;
 import com.codahale.metrics.Timer;
+import com.google.common.annotations.VisibleForTesting;
 import java.awt.Color;
 import java.awt.Dimension;
 import java.awt.Graphics2D;
@@ -161,7 +162,14 @@ private void createTasks(
     if (icons != null && icons.length > 0) {
       for (URL icon : icons) {
         tasks.add(
-            new IconTask(icon, dpi, context, level, tempTaskDirectory, clientHttpRequestFactory));
+            new IconTask(
+                icon,
+                dpi,
+                context,
+                level,
+                tempTaskDirectory,
+                clientHttpRequestFactory,
+                metricRegistry));
       }
     }
     if (legendAttributes.classes != null) {
@@ -269,7 +277,8 @@ protected void extraValidation(
     // no checks needed
   }
 
-  private synchronized BufferedImage getMissingImage() {
+  @VisibleForTesting
+  synchronized BufferedImage getMissingImage() {
     if (this.missingImage == null) {
       this.missingImage =
           new BufferedImage(
@@ -311,7 +320,7 @@ public static final class Output {
     /** The datasource for the legend object in the report. */
     public final JRTableModelDataSource legendDataSource;
 
-    /** The path to the compiled subreport. */
+    /** The path to the compiled sub-report. */
     public final String legendSubReport;
 
     /** The number of rows in the legend. */
@@ -343,7 +352,8 @@ public Object[] call() {
     }
   }
 
-  private final class IconTask implements Callable<Object[]> {
+  @VisibleForTesting
+  final class IconTask implements Callable<Object[]> {
 
     private final URL icon;
     private final double iconDPI;
@@ -351,20 +361,24 @@ private final class IconTask implements Callable<Object[]> {
     private final MfClientHttpRequestFactory clientHttpRequestFactory;
     private final int level;
     private final File tempTaskDirectory;
+    private final MetricRegistry metricRegistry;
 
-    private IconTask(
+    @VisibleForTesting
+    IconTask(
         final URL icon,
         final double iconDPI,
         final ExecutionContext context,
         final int level,
         final File tempTaskDirectory,
-        final MfClientHttpRequestFactory clientHttpRequestFactory) {
+        final MfClientHttpRequestFactory clientHttpRequestFactory,
+        final MetricRegistry metricRegistry) {
       this.icon = icon;
       this.iconDPI = iconDPI;
       this.context = context;
       this.level = level;
       this.clientHttpRequestFactory = clientHttpRequestFactory;
       this.tempTaskDirectory = tempTaskDirectory;
+      this.metricRegistry = metricRegistry;
     }
 
     @Override
@@ -389,8 +403,7 @@ private BufferedImage loadImage(final URI uri) {
           this.context.stopIfCanceled();
           final ClientHttpRequest request =
               this.clientHttpRequestFactory.createRequest(uri, HttpMethod.GET);
-          try (Timer.Context ignored =
-              LegendProcessor.this.metricRegistry.timer(metricName).time()) {
+          try (Timer.Context ignored = metricRegistry.timer(metricName).time()) {
             try (ClientHttpResponse httpResponse = request.execute()) {
               if (httpResponse.getRawStatusCode() == HttpStatus.OK.value()) {
                 image = ImageIO.read(httpResponse.getBody());
@@ -409,7 +422,7 @@ private BufferedImage loadImage(final URI uri) {
 
       if (image == null) {
         image = getMissingImage();
-        LegendProcessor.this.metricRegistry.counter(metricName + ".error").inc();
+        metricRegistry.counter(metricName + ".error").inc();
       }
 
       return image;
diff --git a/core/src/test/java/org/mapfish/print/processor/jasper/IconTaskTest.java b/core/src/test/java/org/mapfish/print/processor/jasper/IconTaskTest.java
new file mode 100644
index 000000000..a6cb2abea
--- /dev/null
+++ b/core/src/test/java/org/mapfish/print/processor/jasper/IconTaskTest.java
@@ -0,0 +1,75 @@
+package org.mapfish.print.processor.jasper;
+
+import static org.junit.Assert.assertEquals;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.when;
+
+import com.codahale.metrics.MetricRegistry;
+import java.awt.image.BufferedImage;
+import java.io.IOException;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.net.URL;
+import java.util.HashMap;
+import org.junit.Test;
+import org.mapfish.print.http.MfClientHttpRequestFactory;
+import org.mapfish.print.processor.AbstractProcessor;
+import org.mapfish.print.processor.Processor;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.mock.http.client.MockClientHttpRequest;
+import org.springframework.mock.http.client.MockClientHttpResponse;
+
+public class IconTaskTest {
+
+  @Test
+  public void call_iconImageDoesNotExist_returnsMissingImageWhenOk() throws Exception {
+    int statusCode = HttpStatus.OK.value();
+    BufferedImage missingImage = new BufferedImage(24, 24, BufferedImage.TYPE_INT_RGB);
+
+    LegendProcessor.IconTask iconTask = prepareTest(missingImage, statusCode);
+
+    Object[] result = iconTask.call();
+
+    assertEquals(missingImage, result[1]);
+  }
+
+  @Test
+  public void call_iconImageDoesNotExist_returnsMissingImageWithUnsupportedStatus()
+      throws Exception {
+    int statusCode = 999;
+    BufferedImage missingImage = new BufferedImage(24, 24, BufferedImage.TYPE_INT_RGB);
+
+    LegendProcessor.IconTask iconTask = prepareTest(missingImage, statusCode);
+
+    Object[] result = iconTask.call();
+
+    assertEquals(missingImage, result[1]);
+  }
+
+  private static LegendProcessor.IconTask prepareTest(BufferedImage missingImage, int statusCode)
+      throws URISyntaxException, IOException {
+    LegendProcessor legendProcessorMock = spy(LegendProcessor.class);
+    when(legendProcessorMock.getMissingImage()).thenReturn(missingImage);
+    Processor.ExecutionContext context = new AbstractProcessor.Context(new HashMap<>());
+    URL icon = mock(URL.class);
+    when(icon.toURI()).thenReturn(new URI("http://localhost/icon.png"));
+    when(icon.getProtocol()).thenReturn("http");
+    MfClientHttpRequestFactory requestFactoryMock = mock(MfClientHttpRequestFactory.class);
+    MockClientHttpRequest requestMock = new MockClientHttpRequest();
+    when(requestFactoryMock.createRequest(any(URI.class), any())).thenReturn(requestMock);
+
+    byte[] responseBody = "Image bytes".getBytes();
+    MockClientHttpResponse responseMock = new MockClientHttpResponse(responseBody, statusCode);
+    responseMock.getHeaders().setContentType(MediaType.IMAGE_PNG);
+    when(requestFactoryMock.createRequest(
+            new URI("testUriString"), org.springframework.http.HttpMethod.GET))
+        .thenReturn(requestMock);
+    requestMock.setResponse(responseMock);
+
+    return legendProcessorMock
+    .new IconTask(icon, 96, context, 1, null, requestFactoryMock, new MetricRegistry());
+  }
+}