/************************************************************************* * Compilation: javac StdOut.java * Execution: java StdOut * * Writes data of various types to standard output. * *************************************************************************/ import java.io.UnsupportedEncodingException; import java.io.PrintWriter; import java.io.OutputStreamWriter; import java.util.Locale; /** * Standard output. This class provides methods for writing strings * and numbers to standard output. *

* For additional documentation, see Section 1.5 of * Introduction to Programming in Java: An Interdisciplinary Approach by Robert Sedgewick and Kevin Wayne. */ public final class StdOut { // force Unicode UTF-8 encoding; otherwise it's system dependent private static final String UTF8 = "UTF-8"; // assume language = English, country = US for consistency with StdIn private static final Locale US_LOCALE = new Locale("en", "US"); // send output here private static PrintWriter out; // this is called before invoking any methods static { try { out = new PrintWriter(new OutputStreamWriter(System.out, UTF8), true); } catch (UnsupportedEncodingException e) { System.out.println(e); } } // singleton pattern - can't instantiate private StdOut() { } // close the output stream (not required) /** * Close standard output. */ public static void close() { out.close(); } /** * Terminate the current line by printing the line separator string. */ public static void println() { out.println(); } /** * Print an object to standard output and then terminate the line. */ public static void println(Object x) { out.println(x); } /** * Print a boolean to standard output and then terminate the line. */ public static void println(boolean x) { out.println(x); } /** * Print a char to standard output and then terminate the line. */ public static void println(char x) { out.println(x); } /** * Print a double to standard output and then terminate the line. */ public static void println(double x) { out.println(x); } /** * Print a float to standard output and then terminate the line. */ public static void println(float x) { out.println(x); } /** * Print an int to standard output and then terminate the line. */ public static void println(int x) { out.println(x); } /** * Print a long to standard output and then terminate the line. */ public static void println(long x) { out.println(x); } /** * Print a short to standard output and then terminate the line. */ public static void println(short x) { out.println(x); } /** * Print a byte to standard output and then terminate the line. */ public static void println(byte x) { out.println(x); } /** * Flush standard output. */ public static void print() { out.flush(); } /** * Print an Object to standard output and flush standard output. */ public static void print(Object x) { out.print(x); out.flush(); } /** * Print a boolean to standard output and flush standard output. */ public static void print(boolean x) { out.print(x); out.flush(); } /** * Print a char to standard output and flush standard output. */ public static void print(char x) { out.print(x); out.flush(); } /** * Print a double to standard output and flush standard output. */ public static void print(double x) { out.print(x); out.flush(); } /** * Print a float to standard output and flush standard output. */ public static void print(float x) { out.print(x); out.flush(); } /** * Print an int to standard output and flush standard output. */ public static void print(int x) { out.print(x); out.flush(); } /** * Print a long to standard output and flush standard output. */ public static void print(long x) { out.print(x); out.flush(); } /** * Print a short to standard output and flush standard output. */ public static void print(short x) { out.print(x); out.flush(); } /** * Print a byte to standard output and flush standard output. */ public static void print(byte x) { out.print(x); out.flush(); } /** * Print a formatted string to standard output using the specified * format string and arguments, and flush standard output. */ public static void printf(String format, Object... args) { out.printf(US_LOCALE, format, args); out.flush(); } /** * Print a formatted string to standard output using the specified * locale, format string, and arguments, and flush standard output. */ public static void printf(Locale locale, String format, Object... args) { out.printf(locale, format, args); out.flush(); } // This method is just here to test the class public static void main(String[] args) { // write to stdout StdOut.println("Test"); StdOut.println(17); StdOut.println(true); StdOut.printf("%.6f\n", 1.0/7.0); } }