Ok, here is my 50 cents. In addition to @ALabrosik and @ReneEnriquez answers.
Download pdf.js dist and place it under src/main/resources
├── pom.xml
├── src
│ └── main
│ ├── java
│ │ └── me
│ │ └── example
│ │ ├── JSLogListener.java
│ │ ├── Launcher.java
│ │ └── WebController.java
│ └── resources
│ ├── build
│ │ ├── pdf.js
│ │ └── pdf.worker.js
│ ├── main.fxml
│ ├── web
│ │ ├── cmaps
│ │ ├── compatibility.js
│ │ ├── debugger.js
│ │ ├── images
│ │ ├── l10n.js
│ │ ├── locale
│ │ ├── viewer.css
│ │ ├── viewer.html
│ │ └── viewer.js
Create the following fxml file (you should wrap WebView in TabPane or similar container to avoid problems with scrolling support)
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.control.Tab?>
<?import javafx.scene.control.TabPane?>
<?import javafx.scene.layout.BorderPane?>
<?import javafx.scene.web.WebView?>
<BorderPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="576.0" prefWidth="1024.0" xmlns="http://javafx.com/javafx/8.0.112" xmlns:fx="http://javafx.com/fxml/1" fx:controller="me.example.WebController">
<center>
<TabPane>
<tabs>
<Tab text="PDF test">
<content>
<WebView fx:id="web" minHeight="-1.0" minWidth="-1.0" />
</content>
</Tab>
</tabs>
</TabPane>
</center>
<bottom>
<Button fx:id="btn" mnemonicParsing="false" text="Open another file" BorderPane.alignment="CENTER" />
</bottom>
</BorderPane>
To prevent pdf.js from opening demo pdf file on startup, open web/viewer.js and clear DEFAULT_URL value.
var DEFAULT_URL = '';
Open web/viewer.html and add script block:
<head>
<!-- ... -->
<script src="viewer.js"></script>
<!-- CUSTOM BLOCK -->
<script>
var openFileFromBase64 = function(data) {
var arr = base64ToArrayBuffer(data);
console.log(arr);
PDFViewerApplication.open(arr);
}
function base64ToArrayBuffer(base64) {
var binary_string = window.atob(base64);
var len = binary_string.length;
var bytes = new Uint8Array( len );
for (var i = 0; i < len; i++) {
bytes[i] = binary_string.charCodeAt(i);
}
return bytes.buffer;
}
</script>
<!-- end of CUSTOM BLOCK -->
</head>
Now the controller (see code comments for explanation).
public class WebController implements Initializable {
@FXML
private WebView web;
@FXML
private Button btn;
public void initialize(URL location, ResourceBundle resources) {
WebEngine engine = web.getEngine();
String url = getClass().getResource("/web/viewer.html").toExternalForm();
// connect CSS styles to customize pdf.js appearance
engine.setUserStyleSheetLocation(getClass().getResource("/web.css").toExternalForm());
engine.setJavaScriptEnabled(true);
engine.load(url);
engine.getLoadWorker()
.stateProperty()
.addListener((observable, oldValue, newValue) -> {
// to debug JS code by showing console.log() calls in IDE console
JSObject window = (JSObject) engine.executeScript("window");
window.setMember("java", new JSLogListener());
engine.executeScript("console.log = function(message){ java.log(message); };");
// this pdf file will be opened on application startup
if (newValue == Worker.State.SUCCEEDED) {
try {
// readFileToByteArray() comes from commons-io library
byte[] data = FileUtils.readFileToByteArray(new File("/path/to/file"));
String base64 = Base64.getEncoder().encodeToString(data);
// call JS function from Java code
engine.executeScript("openFileFromBase64('" + base64 + "')");
} catch (Exception e) {
e.printStackTrace();
}
}
});
// this file will be opened on button click
btn.setOnAction(actionEvent -> {
try {
byte[] data = FileUtils.readFileToByteArray(new File("/path/to/another/file"));
String base64 = Base64.getEncoder().encodeToString(data);
engine.executeScript("openFileFromBase64('" + base64 + "')");
} catch (Exception e) {
e.printStackTrace();
}
});
}
}
Some of pdf.js functions will not work: open file (cause pdf.js have no access to URL outside JAR), printing etc. To hide corresponding toolbar buttons you can add the following lines to web.css:
#toolbarViewerRight {
display:none;
}
That's all. The rest of the code is trivial.
public class JSLogListener {
public void log(String text) {
System.out.println(text);
}
}
public class Launcher extends Application {
public static void main(String[] args) {
Application.launch();
}
public void start(Stage primaryStage) throws Exception {
Parent root = FXMLLoader.load(getClass().getResource("/main.fxml"));
primaryStage.setTitle("PDF test app");
primaryStage.setScene(new Scene(root, 1280, 576));
primaryStage.show();
}
}
Hope this helps to someone.
