javaWeb学习之旅(一)------------java基础知识增强
一、java基础
1.文件的复制
debug调试
F5: step into
F6: step over
F7: step return
思路如下:
java实现的方法如下
[java]
public class Demo1 {
@Test
public static void main(String[] args) {
String file1 = "F:\\test1.txt";
String file2 = "F:\\test.txt";
try {
// 复制
copy(file1, file2);
System.out.println("文件2拷贝成功");
} catch (Exception e) {
// TODO: handle exception
}
}
private static void copy(String file1, String file2) throws Exception {
// 以流的形式读入文件1中的内容
InputStream inputStream = readFile(file1);
writetoFile(inputStream, file2);
}
private static void writetoFile(InputStream inputStream, String file2)
throws IOException {
// TODO Auto-generated method stub
// 如果文件2不存在,则创建文件2
if (!existFile(file2)) {
File file = new File(file2);
file.createNewFile();
}
// 打开文件2 的输出流
FileOutputStream fileOutputStream = new FileOutputStream(file2);
intout(inputStream, fileOutputStream);
}
// 从buffer中读入并写入文件2中
private static void intout(InputStream inputStream,
FileOutputStream fileOutputStream) {
try {
int len = 0;
byte buffer[] = new byte[1024];
while ((len = inputStream.read(buffer)) > 0) {
fileOutputStream.write(buffer, 0, len);
}
} catch (Exception e) {
// TODO: handle exception
} finally {
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (fileOutputStream != null) {
try {
fileOutputStream.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
// TODO Auto-generated method stub
}
// 读文件
private static InputStream readFile(String file1)
throws FileNotFoundException {
// TODO Auto-generated method stub
// 判断文件1存在
if (!existFile(file1)) {
throw new FileNotFoundException("指定的文件不存在");
}
// 向输入流中读文件
FileInputStream inputStream = new FileInputStream(file1);
return inputStream;
}
// 判断文件是否存在
private static boolean existFile(String existfile) {
// TODO Auto-generated method stub
File file = new File(existfile);
if (file.exists()) {
return true;
}
return false;
}
}
public class Demo1 {
@Test
public static void m
补充:Web开发 , 其他 ,