Java Java.io.StringWriter用法及代码示例

// Java program illustrating the working of StringWriter
// class methods write(int char), write(String str), close()
// write(String str, int offset, int maxlen), toString()
// write(char[] carray, int offset, int maxlen)
import java.io.*;
public class NewClass {
    public static void main(String[] args)
        throws IOException
    {
        // Initializing String Writer
        StringWriter geek_writer1 = new StringWriter();
        StringWriter geek_writer2 = new StringWriter();
        StringWriter geek_writer3 = new StringWriter();
        StringWriter geek_writer4 = new StringWriter();
        // Use of write(int char) : to write a character
        geek_writer1.write(71);
        geek_writer1.write(70);
        geek_writer1.write(71);
        // Use of toString() : Value written by write(int
        // char)
        System.out.println("Using write(int char) : "
                           + geek_writer1.toString());
        String str = "Hello Geeks";
        // Use of write(String str) : to write string
        geek_writer2.write(str);
        // Value written by write(String str)
        System.out.println("Using write(String str) : "
                           + geek_writer2.toString());
        // Use of write(String str, int offset, int maxlen)
        // : to write part of string
        geek_writer3.write(str, 2, 4);
        geek_writer3.write(str, 5, 6);
        // Value written by write(String str, int offset,
        // int maxlen)
        System.out.println(
            "Using write(str, offset, maxlen) : "
            + geek_writer3.toString());
        try {
            // Use of Close() method : to close the
            // geek_writer4 But no use as String Writer
            // method is still working with it
            geek_writer4.close();
        }
        catch (IOException except) {
            System.out.println("ERROR");
            except.printStackTrace();
            ;
        }
        // Initializing character array
        char[] carray = str.toCharArray();
        // Use of write(char[] carray, int offset, int
        // maxlen): to write part of char array
        geek_writer4.write(carray, 4, 6);
        // Value written by write(String str, int offset,
        // int maxlen)
        System.out.println(
            "Using write(carray, offset, maxlen) : "
            + geek_writer4.toString());
    }
}

// Java program illustrating the working of StringWriter
// class methods append(CharSequence char_sq), append(char
// Sw) append(CharSequence char_sq, int start,int end)
// flush(), getgetBuffer()
import java.io.*;
public class NewClass {
    public static void main(String[] args)
        throws IOException
    {
        // Initializing String Writer
        StringWriter geek_writer1 = new StringWriter();
        StringWriter geek_writer2 = new StringWriter();
        StringWriter geek_writer3 = new StringWriter();
        // Use of write(int char) : to write a character
        geek_writer1.write(71);
        geek_writer1.write(70);
        geek_writer1.write(71);
        // Use of toString() : Value written by write(int
        // char)
        System.out.println("Using write(int char) : "
                           + geek_writer1.toString());
        // Using flush() method
        geek_writer1.flush();
        System.out.println("Using flush() : "
                           + geek_writer1.toString());
        // Use of append(char Sw)
        System.out.println("append(char Sw) : "
                           + geek_writer1.append(" 1GFG1"));
        // Use of getBuffer() :
        System.out.println("Using geek_writer1 : "
                           + geek_writer1.getBuffer());
        // Initializing Character Sequence
        CharSequence char_sq1 = "1 Hello 1";
        CharSequence char_sq2 = " : 2 Geeks 2";
        // Use of append(CharSequence char_sq)
        geek_writer2.append(char_sq1);
        geek_writer2.append(char_sq2);
        System.out.println("append(char_sq) : "
                           + geek_writer2.toString());
        // Use of append(CharSequence char_sq,int start,int
        // end)
        geek_writer3.append(char_sq1, 0, 3);
        geek_writer3.append(char_sq2, 3, 6);
        System.out.println("append(char_sq,start,end) : "
                           + geek_writer3.toString());
    }
}