RandomAccessFile類readInt()方法 (RandomAccessFile Class readInt() method)

• readInt() method is available in java.io package.

  readInt()方法在java.io包中可用。

• readInt() method is used to read signed 32-bit integer value from this RandomAccessFile.

  readInt()方法用于從此RandomAccessFile讀取帶符號的32位整數值。

• readInt() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.

  readInt()方法是一個非靜態方法，只能通過類對象訪問，如果嘗試使用類名稱訪問該方法，則會收到錯誤消息。

• readInt() method may throw an exception at the time of reading integer.

  readInt()方法在讀取整數時可能會引發異常。

  • IOException: This exception may throw an exception while performing input/output operation.IOException ：在執行輸入/輸出操作時，此異常可能會引發異常。
  • EOFException: This exception may throw when the file pointer reaches EOF (End-Of-File) before reading 4 bytes.EOFException ：當文件指針在讀取4個字節之前到達EOF(文件末尾)時，可能引發此異常。

Syntax:

句法：

    public final int readInt();

Parameter(s):

參數：

• It does not accept any parameter.

  它不接受任何參數。

Return value:

返回值：

The return type of this method is int, it returns the 4 bytes of data from this RandomAccessFile manipulated as an int value.

此方法的返回類型為int ，它從作為Random值操縱的RandomAccessFile中返回4個字節的數據。

Example:

例：

// Java program to demonstrate the example 
// of int readInt() method of
// RandomAccessFile
import java.io.*;
class RAFReadInt {
public static void main(String[] args) throws Exception {
// Instantiate a random access file
// object with file name and permissions
RandomAccessFile ra_f = new RandomAccessFile("e:/includehelp.txt", "rw");
// By using writeFloat() method is to 
// write float to the file
ra_f.writeInt(500);
// Initially set the file pointer
// is at 1 for reading the file
ra_f.seek(1);
// By using readInt() method is to 
// read int upto signed 4 bytes 
// from the file
int i = ra_f.readInt();
System.out.println("ra_f.readInt(): " + i);
// By using close() method isto
// close this stream ran_f
ra_f.close();
}
}

Output

輸出量

ra_f.readInt(): 128210

翻譯自: https://www.includehelp.com/java/randomaccessfile-readint-method-with-example.aspx