Implement open and setLocation method to Page. (vaadin#4869)

flow-server/src/main/java/com/vaadin/flow/component/page/Page.java

@@ -15,14 +15,6 @@
  */
 package com.vaadin.flow.component.page;
 
-import java.io.BufferedReader;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.InputStreamReader;
-import java.io.Serializable;
-import java.nio.charset.StandardCharsets;
-import java.util.Objects;
-
 import com.vaadin.flow.component.ClientCallable;
 import com.vaadin.flow.component.Component;
 import com.vaadin.flow.component.ComponentEvent;
@@ -38,6 +30,15 @@
 import com.vaadin.flow.shared.ui.Dependency.Type;
 import com.vaadin.flow.shared.ui.LoadMode;
 
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.Serializable;
+import java.net.URI;
+import java.nio.charset.StandardCharsets;
+import java.util.Objects;
+
 /**
  * Represents the web page open in the browser, containing the UI it is
  * connected to.
@@ -389,6 +390,80 @@ public Registration addBrowserWindowResizeListener(
         return resizeReceiver.addListener(resizeListener);
     }
 
+    /**
+     * Opens the given url in a new tab.
+     *
+     * @param url
+     *            the URL to open.
+     */
+    public void open(String url) {
+        open(url, "_blank");
+    }
+
+    /**
+     * Opens the given URL in a window with the given name.
+     * <p>
+     * The supplied {@code windowName} is used as the target name in a
+     * window.open call in the client. This means that special values such as
+     * "_blank", "_self", "_top", "_parent" have special meaning. An empty or
+     * <code>null</code> window name is also a special case.
+     * </p>
+     * <p>
+     * "", null and "_self" as {@code windowName} all causes the URL to be
+     * opened in the current window, replacing any old contents. For
+     * downloadable content you should avoid "_self" as "_self" causes the
+     * client to skip rendering of any other changes as it considers them
+     * irrelevant (the page will be replaced by the response from the URL). This
+     * can speed up the opening of a URL, but it might also put the client side
+     * into an inconsistent state if the window content is not completely
+     * replaced e.g., if the URL is downloaded instead of displayed in the
+     * browser.
+     * </p>
+     * <p>
+     * "_blank" as {@code windowName} causes the URL to always be opened in a
+     * new window or tab (depends on the browser and browser settings).
+     * </p>
+     * <p>
+     * "_top" and "_parent" as {@code windowName} works as specified by the HTML
+     * standard.
+     * </p>
+     * <p>
+     * Any other {@code windowName} will open the URL in a window with that
+     * name, either by opening a new window/tab in the browser or by replacing
+     * the contents of an existing window with that name.
+     * </p>
+     *
+     * @param url
+     *            the URL to open.
+     * @param windowName
+     *            the name of the window.
+     */
+    private void open(String url, String windowName) {
+        executeJavaScript("window.open($0, $1)", url, windowName);
+    }
+
+    /**
+     * Navigates this page to the given URI. The contents of this page in the
+     * browser is replaced with whatever is returned for the given URI.
+     *
+     * @param uri
+     *            the URI to show
+     */
+    public void setLocation(String uri) {
+        open(uri, "_self");
+    }
+
+    /**
+     * Navigates this page to the given URI. The contents of this page in the
+     * browser is replaced with whatever is returned for the given URI.
+     *
+     * @param uri
+     *            the URI to show
+     */
+    public void setLocation(URI uri) {
+        setLocation(uri.toString());
+    }
+
     private static class LazyJsLoader implements Serializable {
 
         private static final String JS_FILE_NAME = "windowResizeListener.js";

flow-tests/test-root-context/src/main/java/com/vaadin/flow/uitest/ui/PageView.java

@@ -2,10 +2,14 @@
 
 import com.vaadin.flow.component.html.Div;
 import com.vaadin.flow.component.html.Input;
+import com.vaadin.flow.server.VaadinRequest;
+import com.vaadin.flow.server.VaadinServletRequest;
 import com.vaadin.flow.uitest.servlet.ViewTestLayout;
 import com.vaadin.flow.router.Route;
 import com.vaadin.flow.router.BeforeEnterEvent;
 
+import javax.servlet.http.HttpServletRequest;
+
 @Route(value = "com.vaadin.flow.uitest.ui.PageView", layout = ViewTestLayout.class)
 public class PageView extends AbstractDivView {
 
@@ -38,7 +42,23 @@ public void beforeEnter(BeforeEnterEvent event) {
             getPage().reload();
         });
 
-        add(input, updateButton, overrideButton, reloadButton);
+        VaadinServletRequest request = (VaadinServletRequest) VaadinRequest.getCurrent();
+        HttpServletRequest httpServletRequest = request.getHttpServletRequest();
+        String url = httpServletRequest.getRequestURI()
+                .replace(PageView.class.getName(), BaseHrefView.class.getName());
+
+        Div setLocationButton = new Div();
+        setLocationButton.setId("setLocation");
+        setLocationButton.setText("Set page location");
+        setLocationButton.addClickListener(e -> getPage().setLocation(url));
+
+        Div openButton = new Div();
+        openButton.setId("open");
+        openButton.setText("Open url in a new tab");
+        openButton.addClickListener(e -> getPage().open(url));
+
+        add(input, updateButton, overrideButton, reloadButton,
+                setLocationButton, openButton);
     }
 
 }

flow-tests/test-root-context/src/test/java/com/vaadin/flow/uitest/ui/PageIT.java

@@ -1,12 +1,14 @@
 package com.vaadin.flow.uitest.ui;
 
+import com.vaadin.flow.component.html.testbench.InputTextElement;
+import com.vaadin.flow.testutil.ChromeBrowserTest;
+import org.hamcrest.Matchers;
 import org.junit.Assert;
 import org.junit.Test;
 import org.openqa.selenium.By;
 import org.openqa.selenium.Keys;
 
-import com.vaadin.flow.component.html.testbench.InputTextElement;
-import com.vaadin.flow.testutil.ChromeBrowserTest;
+import java.util.ArrayList;
 
 public class PageIT extends ChromeBrowserTest {
 
@@ -66,4 +68,25 @@ public void testReload() {
         input = $(InputTextElement.class).id("input");
         Assert.assertEquals("", input.getValue());
     }
+
+    @Test
+    public void testSetLocation() {
+        open();
+
+        findElement(By.id("setLocation")).click();
+        Assert.assertThat(getDriver().getCurrentUrl(),
+                Matchers.endsWith(BaseHrefView.class.getName()));
+    }
+
+    @Test
+    public void testOpenUrlInNewTab() {
+        open();
+
+        findElement(By.id("open")).click();
+        ArrayList<String> tabs = new ArrayList<>(getDriver().getWindowHandles());
+        Assert.assertThat(
+                getDriver().switchTo().window(tabs.get(1)).getCurrentUrl(),
+                Matchers.endsWith(BaseHrefView.class.getName())
+        );
+    }
 }