p2p.zip_javatcpp2p开发_tcp实现文件_聊天传文件

package p2p; import java.io.*; import java.util.*; /** * Class for simple console input. A class designed primarily for simple * keyboard input of the form one input value per line. If the user enters an * improper input, i.e., an input of the wrong type or a blank line, then the * user is prompted to reenter the input and given a brief explanation of what * is required. Also includes some additional methods to input single numbers, * words, and characters, without going to the next line. */ public class SavitchIn { /** * Reads a line of text and returns that line as a String value. The end of * a line must be indicated either by a new-line character '\n' or by a * carriage return '\r' followed by a new-line character '\n'. (Almost all * systems do this automatically. So you need not worry about this detail.) * Neither the '\n', nor the '\r' if present, are part of the string * returned. This will read the rest of a line if the line is already * partially read. */ public static String readLine() { char nextChar; String result = ""; boolean done = false; while (!done) { nextChar = readChar(); if (nextChar == '\n') done = true; else if (nextChar == '\r') { // Do nothing. // Next loop iteration will detect '\n'. } else result = result + nextChar; } return result; } /** * Reads the first string of nonwhitespace characters on a line and returns * that string. The rest of the line is discarded. If the line contains only * whitespace, the user is asked to reenter the line. */ public static String readLineWord() { String inputString = null, result = null; boolean done = false; while (!done) { inputString = readLine(); StringTokenizer wordSource = new StringTokenizer(inputString); if (wordSource.hasMoreTokens()) { result = wordSource.nextToken(); done = true; } else { System.out .println("Your input is not correct. Your input must"); System.out .println("contain at least one nonwhitespace character."); System.out.println("Please try again. Enter input:"); } } return result; } /** * Precondition: The user has entered a number of type int on a line by * itself, except that there may be whitespace before and/or after the * number. Action: Reads and returns the number as a value of type int. The * rest of the line is discarded. If the input is not entered correctly, * then in most cases, the user will be asked to reenter the input. In * particular, this applies to incorrect number formats and blank lines. */ public static int readLineInt() { String inputString = null; int number = -9999;// To keep the compiler happy. // Designed to look like a garbage value. boolean done = false; while (!done) { try { inputString = readLine(); inputString = inputString.trim(); number = Integer.parseInt(inputString); done = true; } catch (NumberFormatException e) { System.out.println("Your input number is not correct."); System.out.println("Your input number must be"); System.out.println("a whole number written as an"); System.out.println("ordinary numeral, such as 42"); System.out.println("Minus signs are OK," + "but do not use a plus sign."); System.out.println("Please try again."); System.out.println("Enter a whole number:"); } } return number; } /** * Precondition: The user has entered a number of type long on a line by * itself, except that there may be whitespace before and/or after the * number. Action: Reads and returns the number as a value of type long. The * rest of the line is discarded. If the input is not entered correctly, * then in most cases, the user will be asked to reenter the input. In * particular, this applies to incorrect number formats and blank lines. */ public static long readLineLong() { String inputString = null; long number = -9999;// To keep the compiler happy. // Designed to look like a garbage value. boolean done = false; while (!done) { try { inputString = readLine(); inputString = inputString.trim(); number = Long.parseLong(inputString); done = true; } catch (NumberFormatException e) { System.out.println("Your input number is not correct."); System.out.println("Your input number must be"); System.out.println("a whole number written as an"); System.out.println("ordinary numeral, such as 42"); System.out.println("Minus signs are OK," + "but do not use a plus sign."); System.out.println("Please try again."); System.out.println("Enter a whole number:"); } } return number; } /** * Precondition: The user has entered a number of type double on a line by * itself, except that there may be whitespace before and/or after the * number. Action: Reads and returns the number as a value of type double. * The rest of the line is discarded. If the input is not entered correctly, * then in most cases, the user will be asked to reenter the input. In * particular, this applies to incorrect number formats and blank lines. */ public static double readLineDouble() { String inputString = null; double number = -9999;// To keep the compiler happy. // Designed to look like a garbage value. boolean done = false; while (!done) { try { inputString = readLine(); inputString = inputString.trim(); number = Double.parseDouble(inputString); done = true; } catch (NumberFormatException e) { System.out.println("Your input number is not correct."); System.out.println("Your input number must be"); System.out.println("an ordinary number either with"); System.out.println("or without a decimal point,"); System.out.println("such as 42 or 9.99"); System.out.println("Please try again."); System.out.println("Enter the number:"); } } return number; } /** * Precondition: The user has entered a number of type float on a line by * itself, except that there may be whitespace before and/or after the * number. Action: Reads and returns the number as a value of type float. * The rest of the line is discarded. If the input is not entered correctly, * then in most cases, the user will be asked to reenter the input. In * particular, this applies to incorrect number formats and blank lines. */ public static float readLineFloat() { String inputString = null; float number = -9999;// To keep the compiler happy. // Designed to look like a garbage value. boolean done = false; while (!done) { try { inputString = readLine(); inputString = inputString.trim(); number = Float.parseFloat(inputString); done = true; } catch (NumberFormatException e) { System.out.println("Your input number is not correct."); System.out.println("Your input number must be"); System.out.println("an ordinary number either with"); System.out.println("or without a decimal point,"); System.out.println("such as 42 or 9.99"); System.out.println("Please try again."); System.out.println("Enter the number:"); } } return number; } /** * Reads the first nonwhitespace character on a line and returns that * character. The rest of the line is discarded. If the line contains only * whitespace, the user is asked to reenter the line. */ public static char readLineNonwhiteChar() { boolean done = false; String inputString = null; char nonWhite = ' ';// To keep the compiler happy. while (!done) { inputString = readLine(); inputString = inputString.trim(); if (inputString.length() == 0) { System.out.println("Your input is not correct."); System.out.println("Your input must contain at"); System.out.println("le