从一个文本文件中读取数据
public class FileInputStreamDemo1 { /** * 使用InputStream抽象类的子类FileInputStream类 * 从一个文件中读取流数据 */ public static void test1() { try { FileInputStream myStream = new FileInputStream("src/a.txt"); int a = 0; while((a=myStream.read())!=-1){ //从a.txt读取内容一直到文件的末尾 System.out.PRint((char)a); } myStream.close(); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } public static void main(String[] args) { test1(); }}简单的输出流 输入一个字符到文本中
public class Demo1 { /** * 输入一个字符到文件中 */ public static void test1() { try { OutputStream os = new FileOutputStream("src/b.txt"); os.write(97); os.flush(); os.close(); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } }运行结果为a，因为ascii码97对应的字符为‘a’；输出一个数组/** * 输出一个数组 */ public static void test2() { byte myArray[] = new byte[5]; myArray[0]=97; myArray[1]=98; myArray[2]=99; myArray[3]=100; myArray[4]=101; try { OutputStream os = new FileOutputStream("src/b.txt"); os.write(myArray); os.flush(); os.close(); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } }输出结果为abcde 输出字符串
public static void test3() { String myContent = "I am a good man!"; try { OutputStream os = new FileOutputStream("src/b.txt"); os.write(myContent.getBytes()); os.flush(); os.close(); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } }运行结果为：I am a good man! 。
将一个文件的内容输出到另一个文件中
public static void copy(){ try { FileInputStream myStream = new FileInputStream("src/1.png"); OutputStream os = new FileOutputStream("2.jpg"); int a = 0; while((a = myStream.read())!=-1){ //一直读到文件的末尾 os.write((char)a); } os.flush(); os.close(); } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } }新闻热点
疑难解答
