Java.io.OutputStreamWriter 类方法

OutputStreamWriter类将字符流连接到字节流。它使用指定的字符集将字符编码为字节。
宣言 ：

public class OutputStreamWriter
   extends Writer

构造函数：

• OutputStreamWriter(OutputStream geek_out) ：创建一个“geek_out” OutputStreamWriter，它使用
  用于编码的默认字符集。
• OutputStreamWriter(OutputStream geek_out, Charset geek_set) ：创建一个使用“geek_set”字符集进行编码的“geek_out”OutputStreamWriter。
• OutputStreamWriter(OutputStream geek_out, CharsetEncoder encode) ：创建一个使用给定编码器的“geek_out”OutputStreamWriter。
• OutputStreamWriter(OutputStream geek_out, String setName) ：创建一个使用命名字符集的“geek_out”OutputStreamWriter。

方法：

• flush() : Java.io.OutputStreamWriter.flush()刷新流。
  句法 ：

public void flush()
Parameters : 
------
Return : 
void
Exception : 
-> IOException : if in case anu I/O error occurs.

• close() : Java.io.OutputStreamWriter.close()关闭刷新的流。
  句法 ：

public void close()
Parameters : 
------
Return : 
void
Exception : 
-> IOException : if in case anu I/O error occurs, e.g writing after closing the stream

• write(int char) : Java.io.OutputStreamWriter.write(int char)写入单个字符。
  句法 ：

public void write(int char)
Parameters : 
char : character to be written
Return : 
void

Java

// Java code explaining the working of write(int char), flush(), close()
 
import java.io.*;
public class NewClass
{
    public static void main(String[] args)
    {       
        try
        {
            // Creation of new OutputStreamWriter
            OutputStream g = new FileOutputStream("test.txt");
            OutputStreamWriter geeks_out1 = new OutputStreamWriter(g);
 
            // Creating an Input Stream
            FileInputStream in = new FileInputStream("test.txt");
 
            // Use of write(int char) :
            // Writing character values to the "test.txt"
            geeks_out1.write(71);
            geeks_out1.write(69);
            geeks_out1.write(69);
            geeks_out1.write(75);
            geeks_out1.write(83);
 
            // flush the stream
            geeks_out1.flush();
 
            // read what we write
            for (int i = 0; i < 5; i++)
            {
                // Reading the content of "test.txt" file
                System.out.println("write(int char) : " + (char) in.read());
            }
            geeks_out1.close();
        }
        catch (Exception ex)
        {
            System.out.println("Error");
            ex.printStackTrace();
        }
    }
}

• 输出 ：
  

write(int char) : G
write(int char) : E
write(int char) : E
write(int char) : K
write(int char) : S

• write(String geek, int offset, int strlen) : Java.io.OutputStreamWriter.write(String geek, int offset, int strlen)写入从“偏移位置”开始到“strlen”长度的“geek”字符串的一部分。
  句法 ：

public void write(String geek, int offset, int strlen)
Parameters : 
geek : string whose portion is to be written 
offset : starting position from where to write
strlen : length upto which we need to write
Return : 
void
Exception : 
-> IOException : if in case any I/O error occurs.

Java

// Java code explaining the working of write(String geek, int offset, int strlen))
 
import java.io.*;
public class NewClass
{
    public static void main(String[] args)
    {
        String geek = "GEEKSForGeeks";
        try
        {
            // Creation of new OutputStreamWriter
            OutputStream g = new FileOutputStream("test.txt");
            OutputStreamWriter geeks_out1 = new OutputStreamWriter(g);
 
            // Creating an Input Stream
            FileInputStream in = new FileInputStream("test.txt");
 
            // Use of writewrite(String geek, int offset, int strlen)) :
            // Writing character values to the "test.txt"
            geeks_out1.write(geek, 4, 9);
 
            // flush the stream
            geeks_out1.flush();
 
            // read what we write
            for (int i = 0; i < 5; i++)
            {
                // Reading the content of "test.txt" file
                System.out.println("write(int char) : " + (char) in.read());
            }
            geeks_out1.close();
        }
        catch (Exception ex)
        {
            System.out.println("Error");
            ex.printStackTrace();
        }
    }
}

• 输出 ：
  

write(int char) : S
write(int char) : F
write(int char) : o
write(int char) : r
write(int char) : G

• write(char[] geek, int offset, int strlen) : Java.io.OutputStreamWriter.write(char[] geek, int offset, int strlen)从“偏移位置”开始写入“geek”字符数组的一部分，直到“ strlen”长度。
  句法 ：

public void write(char[] geek, int offset, int strlen)
Parameters : 
geek : character array whose portion is to be written 
offset : starting position from where to write
strlen : length upto which we need to write
Return : 
void
Exception : 
-> IOException : if in case anu I/O error occurs.

• getEncoding() : Java.io.OutputStreamWriter.getEncoding()告诉在提到的 Stream 中使用的字符编码的名称。
  如果存在预定义的名称，则返回，否则返回编码的规范名称。
  如果流已经关闭，则返回 Null。
  句法 ：

public String getEncoding()
Parameters : 
------
Return : 
Name of the charset encoding used
Exception : 
-> IOException : if in case anu I/O error occurs.

Java

// Java code explaining write(char[] geek, int offset, int strlen)
// and getEncoding() method
 
import java.io.*;
public class NewClass
{
    public static void main(String[] args)
    {
        char[] geek = {'G', 'E', 'E', 'K', 'S'};
        try
        {
            // Creation of new OutputStreamWriter
            OutputStream g = new FileOutputStream("test.txt");
            OutputStreamWriter geeks_out1 = new OutputStreamWriter(g);
 
            // Creating an Input Stream
            FileInputStream in = new FileInputStream("test.txt");
 
            // Use of writewrite(char[] geek, int offset, int strlen)) :
            // Writing character values to the "test.txt"
            geeks_out1.write(geek, 0, 3);
 
            // flush the stream
            geeks_out1.flush();
 
            // read what we write
            for (int i = 0; i < 3; i++)
            {
                // Reading the content of "test.txt" file
                System.out.println("char[] geek, int offset, int strlen) : "
                                                            + (char) in.read());
            }
 
            // get and print the encoding for this stream
            System.out.println("\nName of the charset : "
                                        + geeks_out1.getEncoding());
             
            // Closing the OutputStreamWriter
            geeks_out1.close();
        }
         
        catch (Exception ex)
        {
            System.out.println("Error");
            ex.printStackTrace();
        }
    }
}

• 输出 ：
  

char[] geek, int offset, int strlen) : G
char[] geek, int offset, int strlen) : E
char[] geek, int offset, int strlen) : E

Name of the charset : UTF8