1 files changed, 88 insertions, 0 deletions
diff --git a/container-search/src/main/java/com/yahoo/search/pagetemplates/model/Renderer.java b/container-search/src/main/java/com/yahoo/search/pagetemplates/model/Renderer.java
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+++ b/container-search/src/main/java/com/yahoo/search/pagetemplates/model/Renderer.java
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+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.search.pagetemplates.model;
+
+import com.yahoo.component.provider.FreezableClass;
+import com.yahoo.protect.Validator;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+/**
+ * A description of a way to present data items from a source.
+ * All data items has a default renderer. This can be overridden or parametrized by
+ * an explicit renderer.
+ *
+ * @author <a href="mailto:bratseth@yahoo-inc.com">Jon Bratseth</a>
+ */
+public final class Renderer extends FreezableClass implements PageElement {
+
+    private String name;
+
+    private String rendererFor;
+
+    private Map<String,String> parameters =new LinkedHashMap<>();
+
+    public Renderer(String name) {
+        setName(name);
+    }
+
+    /**
+     * Returns the name of this renderer (never null).
+     * The name should be recognized by the system receiving results for rendering
+     */
+    public String getName() { return name; }
+
+    public final void setName(String name) {
+        ensureNotFrozen();
+        Validator.ensureNotNull("renderer name",name);
+        this.name=name;
+    }
+
+    /**
+     * Returns the name of the kind of data this is a renderer for.
+     * This is used to allow frontends to dispatch the right data items (hits) to
+     * the right renderer in the case where the data consists of a heterogeneous list.
+     * <p>
+     * This is null if this is a renderer for a whole section, or if this is a renderer
+     * for all kinds of data from a particular source <i>and</i> this is not frozen.
+     * <p>
+     * Otherwise, it is either the name of the source this is the renderer for,
+     * <i>or</i> the renderer for all data items having this name as a <i>type</i>.
+     * <p>
+     * This, a (frontend) dispatcher of data to renderers should for each data item:
+     * <ul>
+     *     <li>use the renderer having the same name as any <code>type</code> name set of the data item
+     *     <li>if no such renderer, use the renderer having <code>rendererFor</code> equal to the data items <code>source</code>
+     *     <li>if no such renderer, use a default renderer
+     * </ul>
+     */
+    public String getRendererFor() { return rendererFor; }
+
+    public void setRendererFor(String rendererFor) {
+        ensureNotFrozen();
+        this.rendererFor=rendererFor;
+    }
+
+    /**
+     * Returns the parameters of this renderer as a live reference (never null).
+     * The parameters will be passed to the renderer with each result
+     */
+    public Map<String,String> parameters() { return parameters; }
+
+    public @Override void freeze() {
+        if (isFrozen()) return;
+        super.freeze();
+        parameters = Collections.unmodifiableMap(parameters);
+    }
+
+    /** Accepts a visitor to this structure */
+    public @Override void accept(PageTemplateVisitor visitor) {
+        visitor.visit(this);
+    }
+     public @Override String toString() {
+        return "renderer '" + name + "'";
+    }
+
+}