JAVA中纯文本的读与写、拷贝

古城微笑少年丶 2022-06-17 12:19 124阅读 0赞

字符流：只能处理纯文本、全部为可见字符、txt、html

节点流：Reader FileReader、Writer  FileWriter

读取纯文本步骤与代码：

public class ReadDemo {
           /**
            * 1.创建源   File对象
            * 2.选择流   Reader FileReader
            * 3.操作            read()
            * 4.释放资源 关闭流
            */
           public static void main(String[] args){
                  File src = new File("C:/Users/Administrator/Desktop/android学习笔记/a.txt");
                  Reader reader = null;
                  try {
                         reader = new FileReader(src);
                         char[] test = new char[1024];
                         int len = 0;
                         while(-1!=(len=reader.read(test))){
                               String string = new String(test, 0, len);
                               System.out.println(string);
                         }
                  } catch (FileNotFoundException e) {
                         // TODO Auto-generated catch block
                         e.printStackTrace();
                         System.out.println("文件不存在");
                  } catch (IOException e) {
                         // TODO Auto-generated catch block
                         e.printStackTrace();
                         System.out.println("读取文件失败");
                  }finally {
                         if(null!=reader){
                               try {
                                      reader.close();
                               } catch (IOException e) {
                                      // TODO Auto-generated catch block
                                      e.printStackTrace();
                                      System.out.println("关闭文件失败");
                               }
                         }
                  }
           }
    
    }

纯文本的写出：

public class WriteDemo {
           /**
            * 1.创建源   File对象
            * 2.选择流   Writer FileWriter
            * 3.操作            Write(str) ; append(char c);
            * 4.释放资源 关闭流
            */
           public static void main(String[] args){
                  File dest = new File("C:/Users/Administrator/Desktop/android学习笔记/a_write.txt");
                  Writer writer = null;
                  try {
                         writer = new FileWriter(dest);
                         String string = new String("Hello!Writer");
                         writer.write(string);
                         writer.append("测试测试");
                         writer.flush();
                  } catch (FileNotFoundException e) {
                         // TODO Auto-generated catch block
                         e.printStackTrace();
                  } catch (IOException e) {
                         // TODO: handle exception
                         e.printStackTrace();
                  }finally {
                         if(null!=writer){
                               try {
                                      writer.close();
                               } catch (IOException e) {
                                      // TODO Auto-generated catch block
                                      e.printStackTrace();
                               }
                         }
                  }
           }
    }

纯文本的拷贝：

public class CopyDemo {
           /**
            * 纯文本的拷贝
            * 1.建立联系        File对象
            * 2.选择流   Reader FileReader   Writer FileWriter
            * 3.操作            char[] test = new char[20];
            *                   定义每次实际读的长度；
            *                   while语句循环读取完文件数据{
            *                         writer.write();
            *                         writer.flush();
            *                   }
            * 4.释放资源 关闭流
            */
           public static void main(String[] args){
                  File src = new File("C:/Users/Administrator/Desktop/android学习笔记/a.txt");
                  File dest = new File("C:/Users/Administrator/Desktop/android学习笔记/a_copy.txt");
                  Reader reader = null;
                  Writer writer = null;
                  try {
                  reader = new FileReader(src);
                  writer = new FileWriter(dest);
                  char[] test = new char[1024];
                  int len =0;
                  while(-1!=(len=reader.read(test))){
                               writer.write(test, 0, len);
                               writer.flush();
                         }
                  } catch (FileNotFoundException e) {
                         // TODO Auto-generated catch block
                         e.printStackTrace();
                  }catch (IOException e) {
                         // TODO Auto-generated catch block
                         e.printStackTrace();
           }finally {
                  try {
                         writer.close();
                  } catch (IOException e) {
                         // TODO Auto-generated catch block
                         e.printStackTrace();
                  }
                  try {
                         reader.close();
                  } catch (IOException e) {
                         // TODO Auto-generated catch block
                         e.printStackTrace();
                  }
           }
    }
    }