Java Java类设置 2

Java Java类设置 1
更多方法：

PrintStream printf(Locale l, String format, Object... args) ：一种使用指定格式字符串和参数将格式化字符串写入此输出流的便捷方法。

Syntax :public PrintStream printf(Locale l,
                 String format,
                 Object... args)
Parameters:
l - The locale to apply during formatting. If l is null then no localization is applied.
format - A format string as described in Format string syntax
args - Arguments referenced by the format specifiers in the format string.
Returns:
This output stream
Throws:
IllegalFormatException 
NullPointerException

//Java program to demonstrate printf method
import java.io.*;
import java.util.Locale;
  
class PrintStreamDemo 
{
    public static void main(String[] args) 
    {
        String s = "for";
          
        // create printstream object
        PrintStream printStream = new PrintStream(System.out);
          
        // illustrating printf(Locale l, String format, Object... args) method
        printStream.printf(Locale.US, "Geeks%sGeeks", s);
    }
}

Output:
GeeksforGeeks

PrintStream printf(String format, Object... args) ：一种使用指定格式字符串和参数将格式化字符串写入此输出流的便捷方法。

Syntax :public PrintStream printf(String format,
                 Object... args)
Parameters:
format - A format string as described in Format string syntax
args - Arguments referenced by the format specifiers in the format string.
Returns:
This output stream
Throws:
IllegalFormatException 
NullPointerException

//Java program to demonstrate printf(String format, Object... args) method
import java.io.*;
  
public class PrintStreamDemo 
{
    public static void main(String[] args)
    {
        String s = "for";
          
        // create printstream object
        PrintStream obj= new PrintStream(System.out);
          
        // illustrating printf(String format, Object... args) method
        obj.printf("Geeks%sGeeks", s);
    }
}

Output:
GeeksforGeeks

void println()：通过写入行分隔符字符串来终止当前行。

Syntax :public void println()

//Java program to demonstrate println() methods
import java.io.PrintStream;
  
class PrintStreamDemo
{
    public static void main(String[] args)
    {
        PrintStream obj = new PrintStream(System.out);
          
        //illustrating println();
        obj.println("GeeksforGeeks");
    }
}

Output:
GeeksforGeeks

void println(boolean x)：打印一个布尔值，然后终止该行。

Syntax :public void println(boolean x)

//Java program to demonstrate println(boolean) method
import java.io.*;
  
class PrintStreamDemo 
{
    public static void main(String[] args) 
    {
        // create printstream object
        PrintStream obj = new PrintStream(System.out);
  
        //illustrating println(boolean) method
        obj.println(true);
  
        // flush the stream
        obj.flush();
    }
}

Output:
true

void println(char x)：打印一个字符，然后终止该行。

Syntax :public void println(char x)

//Java program to demonstrate println(char x) method
import java.io.*;
  
public class PrintStreamDemo 
{
    public static void main(String[] args) 
    {
        char c = 'g';
          
        // create printstream object
        PrintStream obj = new PrintStream(System.out);
          
        // illustrating println(char x)
        obj.println(c);
          
        // flush the stream
        obj.flush();
      
    }
}

Output:
g

void println(char[] x)：打印一个字符数组，然后终止该行。

Syntax :public void println(char[] x)

//Java program to demonstrate println(char[] x) method
import java.io.*;
  
public class PrintStreamDemo 
{
    public static void main(String[] args) 
    {
        char[] c = {'G', 'E', 'E','K'};
      
        // create printstream object
        PrintStream obj = new PrintStream(System.out);
      
        // illustrating println(char[] x)
        obj.println(c);
      
        // flush the stream
        obj.flush();
    }
}

Output:
GEEK

void println(double x)：打印一个双精度然后终止该行。

Syntax :public void println(double x)

//Java program to demonstrate println(double x) method
import java.io.*;
  
public class PrintStreamDemo
{
    public static void main(String[] args) 
    {
        double c = 5.42762;
          
        // create printstream object
        PrintStream obj = new PrintStream(System.out);
          
        // illustrating println(double x)
        obj.println(c);
          
        // flush the stream
        obj.flush();
    }
}

输出：

5.42762

void println(float x)：打印一个浮点数，然后终止该行。

Syntax :public void println(float x)

//Java program to demonstrate println(float x) method
import java.io.*;
public class PrintStreamDemo
{
    public static void main(String[] args) 
    {
        float c = 5.168502f;
          
        // create printstream object
        PrintStream obj = new PrintStream(System.out);
      
        // illustrating println(float x)
        obj.println(c);
          
        // flush the stream
        obj.flush();
    }
}

输出：

5.168502f

void println(int x)：打印一个整数，然后终止该行。

Syntax :public void println(boolean x)

//Java program to demonstrate println(int x) method
import java.io.*;
  
public class PrintStreamDemo
{
    public static void main(String[] args)
    {
          
        int c = 5;
          
        // create printstream object
        PrintStream obj = new PrintStream(System.out);
          
        // illustrating println(int x)
        obj.println(c);
          
        // flush the stream
        obj.flush();
    }
}

输出：

void println(long x)：打印一个 long 然后终止该行。

Syntax :public void println(long x)

//Java program to demonstrate println(long x) method
  
import java.io.*;
public class PrintStreamDemo 
{
    public static void main(String[] args)
    {
        long c = 123456789l;
        try 
        {
            // create printstream object
            PrintStream obj= new PrintStream(System.out);
              
            // illustrating println(long x)
            obj.println(c);
              
            // flush the stream
            obj.flush();
        }
        catch (Exception ex)
        {
            ex.printStackTrace();
        }
    }
}

输出：

123456789

void println(Object x) ：打印一个对象，然后终止该行。

Syntax :public void println(Object x)

//Java program to demonstrate println(Object x) method
import java.io.*;
  
public class PrintStreamDemo 
{
      
    public static void main(String[] args) 
    {
        // create printstream object
        PrintStream obj = new PrintStream(System.out);
          
        //illustrating println(Object X)
        obj.println(obj);
          
        // flush the stream
        obj.flush();
    }
}

输出：

java.io.PrintStream@15db9742

void println(String x) ：打印一个字符串，然后终止该行。

Syntax :public void println(boolean x)

import java.io.*;
import java.io.*;
//Java program to demonstrate println(String x) method
public class PrintStreamDemo 
{
    public static void main(String[] args) 
    {
        String c = "GeeksforGeeks";
          
        // create printstream object
        PrintStream ps = new PrintStream(System.out);
          
        // illustrating println(String x)
        ps.println(c);
          
        // flush the stream
        ps.flush();
    }
}

输出：

GeeksforGeeks

protected void setError() ：将流的错误状态设置为 true。

Syntax :public void println(String x)

//Java program to demonstrate setError() method
import java.io.*;
  
public class PrintStreamDemo extends PrintStream 
{
    public PrintStreamDemo(OutputStream out) 
    {
        super(out);
    }
    public static void main(String[] args) 
    {
        byte c[] = {65, 66, 67, 68, 69, 70, 71};
          
        // create printstream object
        PrintStreamDemo obj = new PrintStreamDemo(System.out);
          
        // illustrating write() method
        obj.write(c, 1, 3);
          
        // flush the stream
        obj.flush();
          
        //illustrating setError() method 
        obj.setError();
    }
}

输出：

BCD

void write(byte[] buf, int off, int len) ：从偏移量 off 开始的指定字节数组中写入 len 个字节到此流。

Syntax :public void write(byte[] buf,
         int off,
         int len)
Overrides:
write in class FilterOutputStream
Parameters:
buf - A byte array
off - Offset from which to start taking bytes
len - Number of bytes to write

//Java program to demonstrate write(int b) method
import java.io.*;
  
public class PrintStreamDemo 
{
    public static void main(String[] args) 
    {
        byte c = 65;
      
        // create printstream object
        PrintStream obj = new PrintStream(System.out);
          
        //illustrating write(int b)
        obj.write(c);
      
        // flush the stream
        obj.flush();
      
    }
}

输出：

BCD

void write(int b) ：将指定的字节写入此流。

Syntax :public void write(int b)
Overrides:
write in class FilterOutputStream
Parameters:
b - The byte to be written

//Java program to demonstrate write(int b) method
import java.io.*;
  
public class PrintStreamDemo 
{
    public static void main(String[] args) 
    {
        byte c = 65;
          
        // create printstream object
        PrintStream obj = new PrintStream(System.out);
          
        //illustrating write(int b)
        obj.write(c);
          
        // flush the stream
        obj.flush();
      
    }
}

输出：