Scanner对象,它附属于”标准输入流 Scanner in = new Scanner(System.in); 现在我们就可以使用Scanner...
http://www.baeldung.com/java-read-file Java – Read from File 1. Overview In this tutorial we’ll explore different ways to read from a File in Java; we’ll make use ofBufferedReader, Scanner, StreamTokenizer, DataInputStream, SequenceInputStream andFileChannel. Then, we will discuss how ...
public void whenReadWithScanner_thenCorrect() throws IOException { String file = "src/test/resources/fileTest.txt"; Scanner scanner = new Scanner(new File(file)); scanner.useDelimiter(","); assertTrue(scanner.hasNext()); assertEquals("Hello", scanner.next()); assertEquals("World!", scanner....
@TestpublicvoidwhenReadWithScanner_thenCorrect()throwsIOException{ String file ="src/test/resources/fileTest.txt"; Scanner scanner =newScanner(newFile(file)); scanner.useDelimiter(" "); assertTrue(scanner.hasNext()); assertEquals("Hello,", scanner.next()); assertEquals("world!", scanner.next()...
上面例程里使用了Scanner,以命令行交互的方式让我们能输入程序将要创建文件的名称和要往文件里写入的内容。 Java 的 IO流在使用完成后需要统一调用close()方法把流关闭掉。IO流的关闭会让程序释放出它们占用的内存资源,而且字符流操作时使用了缓冲区,并在关闭字符流时会强制将缓冲区内容输出,如果不关闭流,则缓冲区...
1.Scanner Scanner类提供了用Java逐行读取文件的最简单方法。 我们可以使用Scanner类打开文件,然后逐行读取其内容。 Scanner程序使用定界符模式将其输入分为令牌,在本例中为新行: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 try{// open file to readScanner scanner=newScanner(newFile("examplefile.txt"...
First, we’ll learn how to load a file from the classpath, a URL, or from a JAR file using standard Java classes. Second, we’ll see how to read the content withBufferedReader,Scanner,StreamTokenizer,DataInputStream,SequenceInputStream,andFileChannel. We will also discuss how to read a ...
我们还知道,这个字符串可以换做任意实现了Readable接口的类所生成的对象。这时候我们就需要自己完成继承自Readable中的read()方法。 那么时候,其read()方法是如何被Scanner中的方法所调用的呢? 观察如下代码: //: interfaces/RandomWords.java // Implementing an interface to conform to a method. ...
For example, this code allows a user to read a number from System.in: Scanner sc = new Scanner(System.in); int i = sc.nextInt(); As another example, this code allows long types to be assigned from entries in a file myNumbers: Scanner sc = new Scanner(new File("myNumbers"))...
packagecom.journaldev.readfileslinebyline;importjava.io.File;importjava.io.FileNotFoundException;importjava.util.Scanner;publicclassReadFileLineByLineUsingScanner{publicstaticvoidmain(String[]args){try{Scannerscanner=newScanner(newFile("sample.txt"));while(scanner.hasNextLine()){System.out.println(scann...