1.2.17

README.md

@@ -1,6 +1,6 @@
 # Java to JavaScript (java2js)
 
-java2js can translate simple Java programs to JavaScript and runs them using a JavaScript based JDK.
+java2js can translate simple Java programs to JavaScript and runs them using a JavaScript based JDK in the browser without the use of a VM on a server.
 
 [Try it out!](https://quinton-ashley.github.io/java2js/) The demo files are located in the docs folder of this repository, its a barebones implementation that shows what is possible with java2js.
 

ide.js

@@ -15,3 +15,82 @@
 
 	run();
 })();
+
+// Adds support for tabs in the textarea.
+// https://css-tricks.com/snippets/javascript/support-tabs-in-textareas/
+
+HTMLTextAreaElement.prototype.getCaretPosition = function () {
+	//return the caret position of the textarea
+	return this.selectionStart;
+};
+HTMLTextAreaElement.prototype.setCaretPosition = function (position) {
+	//change the caret position of the textarea
+	this.selectionStart = position;
+	this.selectionEnd = position;
+	this.focus();
+};
+HTMLTextAreaElement.prototype.hasSelection = function () {
+	//if the textarea has selection then return true
+	if (this.selectionStart == this.selectionEnd) {
+		return false;
+	} else {
+		return true;
+	}
+};
+HTMLTextAreaElement.prototype.getSelectedText = function () {
+	//return the selection text
+	return this.value.substring(this.selectionStart, this.selectionEnd);
+};
+HTMLTextAreaElement.prototype.setSelection = function (start, end) {
+	//change the selection area of the textarea
+	this.selectionStart = start;
+	this.selectionEnd = end;
+	this.focus();
+};
+
+var textarea = document.getElementsByTagName('textarea')[0];
+
+textarea.onkeydown = function (event) {
+	//support tab on textarea
+	if (event.keyCode == 9) {
+		//tab was pressed
+		var newCaretPosition;
+		newCaretPosition = textarea.getCaretPosition() + '    '.length;
+		textarea.value =
+			textarea.value.substring(0, textarea.getCaretPosition()) +
+			'    ' +
+			textarea.value.substring(textarea.getCaretPosition(), textarea.value.length);
+		textarea.setCaretPosition(newCaretPosition);
+		return false;
+	}
+	if (event.keyCode == 8) {
+		//backspace
+		if (textarea.value.substring(textarea.getCaretPosition() - 4, textarea.getCaretPosition()) == '    ') {
+			//it's a tab space
+			var newCaretPosition;
+			newCaretPosition = textarea.getCaretPosition() - 3;
+			textarea.value =
+				textarea.value.substring(0, textarea.getCaretPosition() - 3) +
+				textarea.value.substring(textarea.getCaretPosition(), textarea.value.length);
+			textarea.setCaretPosition(newCaretPosition);
+		}
+	}
+	if (event.keyCode == 37) {
+		//left arrow
+		var newCaretPosition;
+		if (textarea.value.substring(textarea.getCaretPosition() - 4, textarea.getCaretPosition()) == '    ') {
+			//it's a tab space
+			newCaretPosition = textarea.getCaretPosition() - 3;
+			textarea.setCaretPosition(newCaretPosition);
+		}
+	}
+	if (event.keyCode == 39) {
+		//right arrow
+		var newCaretPosition;
+		if (textarea.value.substring(textarea.getCaretPosition() + 4, textarea.getCaretPosition()) == '    ') {
+			//it's a tab space
+			newCaretPosition = textarea.getCaretPosition() + 3;
+			textarea.setCaretPosition(newCaretPosition);
+		}
+	}
+};

index.html

@@ -56,10 +56,25 @@
 			autocapitalize="off"
 			placeholder="Create a Java class with a main method here..."
 		>
-public class HelloWorld {
+package tests;
-  public static void main(String[] args){
+
-    System.out.println("hello world!");
+import java.util.Scanner;
-  }
+
+public class ScannerTest {
+	public static void main(String[] args) {
+		Scanner sc = new Scanner(System.in);
+		System.out.println("Hello world!");
+
+		System.out.print("What's your name: ");
+		String name = sc.nextLine();
+		System.out.println("Hello " + name);
+
+		System.out.print("What's your favorite number: ");
+		int age = sc.nextInt();
+		System.out.println(age + "? That's my favorite too!");
+
+		sc.close();
+	}
 }
 </textarea
 		>

jdk.js

@@ -95,9 +95,6 @@
 							window[name] = this.java.lang[name];
 						}
 
-						System.in.reset();
-						System.out.reset();
-
 						// stub main
 						this.main = () => {
 							console.error('No main method found in loaded classes!');
@@ -105,6 +102,10 @@
 					}
 
 					run(jvmArgs) {
+						// reset
+						System.in.reset();
+						System.out.reset();
+
 						this.main(jvmArgs);
 					}
 

jdk/java/util/Scanner.js

@@ -24,29 +24,31 @@ jdk.imports['java.util.Scanner'].load = async () => {
 			if (this._loading) {
 				await this._loadFile(this._filePath);
 			}
+			let s = this.in.stream.slice(this.in.mark);
+			if (!s) return;
 			if (pattern instanceof RegExp) {
-				return pattern.test(this.in.stream.slice(this.in.mark));
+				return pattern.test(s);
 			}
 			// if pattern is string
-			return this.in.stream.slice(this.in.mark).includes(pattern);
+			return s.includes(pattern);
 		}
 		hasNextLine() {
 			return this.hasNext('\n');
 		}
 		nextLine() {
-			return this.next(/.*/);
+			return this.next(/(.*)\r*\n/);
 		}
 		async next(pattern) {
 			while (this._loading || !(await this.hasNext(pattern))) {
 				await new Promise((resolve) => setTimeout(resolve, 100));
 			}
 			let buf = this.in.stream.slice(this.in.mark);
-			let substr = buf.match(pattern)[0];
-			let start = buf.indexOf(substr);
 			let end = buf.indexOf('\n');
-			if (end == -1) {
+			let substr = buf.match(pattern)[1];
+			if (!substr || end == -1) {
 				throw 'NoSuchElementException: No ' + pattern.toString() + ' found in buffer ' + buf;
 			}
+			let start = buf.indexOf(substr);
 			this.in.read(end - start + 1);
 			return buf.slice(start, substr.length);
 		}
@@ -54,13 +56,13 @@ jdk.imports['java.util.Scanner'].load = async () => {
 			return this.nextInt();
 		}
 		async nextInt() {
-			return Number(await this.next(/\d+/));
+			return Number(await this.next(/(\d+)\r*\n/));
 		}
 		nextLong() {
 			return this.nextInt();
 		}
 		async nextFloat() {
-			return Number(await this.next(/[0-9\.]+/));
+			return Number(await this.next(/([0-9\.]+)\r*\n/));
 		}
 		nextDouble() {
 			return this.nextFloat();

package.json

@@ -1,6 +1,6 @@
 {
 	"name": "java2js",
-	"version": "1.2.16",
+	"version": "1.2.17",
 	"description": "Converts Java to JavaScript and runs it with a JS JDK",
 	"main": "jdk.js",
 	"scripts": {

tests/ScannerTest.java

@@ -0,0 +1,20 @@
+package tests;
+
+import java.util.Scanner;
+
+public class ScannerTest {
+	public static void main(String[] args) {
+		Scanner sc = new Scanner(System.in);
+		System.out.println("Hello world!");
+
+		System.out.print("What's your name: ");
+		String name = sc.nextLine();
+		System.out.println("Hello " + name);
+
+		System.out.print("What's your favorite number: ");
+		int age = sc.nextInt();
+		System.out.println(age + "? That's my favorite too!");
+
+		sc.close();
+	}
+}