Java Writer append(CharSequence, int, int)方法及实例

Java中Writer类的append(CharSequence, int, int)方法用于在Writer上追加指定charSequence的指定部分。这个charSequence被作为一个参数。要写入的起始索引和结束索引也被作为参数。

语法。

public void append(CharSequence charSequence, int startingIndex, int endingIndex)

参数。该方法接受三个强制性参数。

charSequence是要写入流中的charSequence。
startingIndex是起始索引，将从该部分字符中提取。
endingIndex是要写在写入器上的结束索引。

返回值。这个方法不返回任何值。

下面的方法说明了append(CharSequence, int, int)方法的工作。

程序1:

// Java program to demonstrate
// Writer append(CharSequence, int, int) method
  
import java.io.*;
  
class GFG {
    public static void main(String[] args)
    {
  
        try {
  
            // Create a Writer instance
            Writer writer
                = new PrintWriter(System.out);
  
            // Get the charSequence
            // to be written in the writer
            CharSequence charSequence = "GeeksForGeeks";
  
            // Get the starting index
            int startingIndex = 0;
  
            // Get the length of char
            int endingIndex = 5;
  
            // Write the portion of the charSequence
            // to this writer using append() method
            // This will put the charSequence in the writer
            // till it is printed on the console
            writer.append(charSequence,
                          startingIndex,
                          endingIndex);
  
            writer.flush();
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }
}

输出:

Geeks

程序2。

// Java program to demonstrate
// Writer append(CharSequence, int, int) method
  
import java.io.*;
  
class GFG {
    public static void main(String[] args)
    {
  
        try {
  
            // Create a Writer instance
            Writer writer
                = new PrintWriter(System.out);
  
            // Get the charSequence
            // to be written in the writer
            CharSequence charSequence = "GFG";
  
            // Get the starting index
            int startingIndex = 2;
  
            // Get the length of char
            int endingIndex = 3;
  
            // Write the portion of the charSequence
            // to this writer using append() method
            // This will put the charSequence in the writer
            // till it is printed on the console
            writer.append(charSequence,
                          startingIndex,
                          endingIndex);
  
            writer.flush();
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }
}

输出: