Java InputStreamReader close()用法及代碼示例

InputStreamReader類close()方法

• close() 方法可在java.io包。
• close() 方法用於關閉此 InputStreamReader 流並釋放與此流鏈接的所有係統資源。
• close() 方法是一個非靜態方法，它隻能通過類對象訪問，如果我們嘗試使用類名訪問方法，那麽我們將得到一個錯誤。
• close() 方法可能會在關閉流時拋出異常。
  IOException:在執行時遇到任何輸入/輸出錯誤時可能會拋出此異常。

用法:

    public void close();

參數：

• 它不接受任何參數。

返回值：

該方法的返回類型是void，它什麽都不返回。

例：

// Java program to demonstrate the example 
// of void close() method of InputStreamReader

import java.io.*;
public class CloseOfISR {
 public static void main(String[] args) throws Exception {
  InputStream is_stm = null;
  InputStreamReader isr_stm = null;
  int val = 0;

  try {
   // Instantiates FileInputStream and InputStreamReader 
   is_stm = new FileInputStream("D:\\includehelp.txt");
   isr_stm = new InputStreamReader(is_stm);

   // By using close() method is to close
   // close the stream     
   isr_stm.close();

   // when we call read() method after
   // closing the stream will result an exception
   val = isr_stm.read();

  } catch (Exception ex) {
   System.out.println("Stream Closed Before!!!!");
  } finally {
   // with the help of this block is to
   // free all necessary resources linked
   // with the stream
   if (is_stm != null) {
    is_stm.close();

    if (isr_stm != null) {
     isr_stm.close();
    }
   }
  }
 }
}

輸出

Stream Closed Before!!!!