Head first java 第五章（一）

Dotcom游戏

实现一个战舰类的棋牌游戏
1.0 首先写出一个测试代码SimpleDotComTestDrive(该版本为最简易版本，无需输入)

public class SimpleDotComTestDrive {    public static void main (String[] args){        SimpleDotCom dot = new SimpleDotCom();  //创建实例对象        int [] locations = {2,3,4};  //假设目标坐标        dot.setLocationCells(locations);  //为实例对象设置坐标        String userGuess = "2";  //假设游戏者输入坐标2        String result = dot.checkYourself(userGuess);   //使用checkYourself方法检查    }}

根据测试码可知运行该游戏后，输出为hit

真实码

public class SimpleDotCom {    int [] locationCells;  //目标数组    int numOfHits = 0;      public void setLocationCells(int[] locs){        locationCells = locs;    }    public String checkYourself(String stringGuess){        int guess = Integer.parseInt(stringGuess);  //Sting转换为int        String result = "miss";          for(int cell : locationCells){            if(guess == cell){                result = "hit";                numOfHits++;                break;            }  //循环检查目标坐标是否等于输入坐标        }        if(numOfHits == locationCells.length){            result = "kill";        }        System.out.println(result);        return result;    }}

2.0 仍然保留SimpleDotCom类，删除SimpleDotComTestDrive类，另外加入SimpleDotComGame类，该类代码如下：

package game;public class SimpleDotComGame {    public static void main (String[] args){    int numOfGuesses = 0;    GameHelper helper = new GameHelper();    SimpleDotCom theDotCom = new SimpleDotCom();    int radomNum = (int) (Math.random()*5);    int[] locations = {radomNum,radomNum+1,radomNum+2};    theDotCom.setLocationCells(locations);    boolean isAlive = true;    while (isAlive == true){        String guess = helper.getUserInput("你猜");        String result = theDotCom.checkYourself(guess);        numOfGuesses++;        if(result.equals("kill")){            isAlive = false;            System.out.println("你猜了"+numOfGuesses);        }    }}}

以及GameHelper类：（该部分代码为copy，暂且不管）

package game;import java.io.*;import java.util.*;public class GameHelper {  private static final String alphabet = "abcdefg";  private int gridLength = 7;  private int gridSize = 49;  private int [] grid = new int[gridSize];  private int comCount = 0;  public String getUserInput(String prompt) {     String inputLine = null;     System.out.print(prompt + "  ");     try {       BufferedReader is = new BufferedReader(     new InputStreamReader(System.in));       inputLine = is.readLine();       if (inputLine.length() == 0 )  return null;      } catch (IOException e) {       System.out.println("IOException: " + e);     }     return inputLine.toLowerCase();  } public ArrayList<String> placeDotCom(int comSize) {                 // line 19    ArrayList<String> alphaCells = new ArrayList<String>();    String [] alphacoords = new String [comSize];      // holds 'f6' type coords    String temp = null;                                // temporary String for concat    int [] coords = new int[comSize];                  // current candidate coords    int attempts = 0;                                  // current attempts counter    boolean success = false;                           // flag = found a good location ?    int location = 0;                                  // current starting location    comCount++;                                        // nth dot com to place    int incr = 1;                                      // set horizontal increment    if ((comCount % 2) == 1) {                         // if odd dot com  (place vertically)      incr = gridLength;                               // set vertical increment    }    while ( !success & attempts++ < 200 ) {             // main search loop  (32)    location = (int) (Math.random() * gridSize);      // get random starting point        //System.out.print(" try " + location);    int x = 0;                                        // nth position in dotcom to place        success = true;                                 // assume success        while (success && x < comSize) {                // look for adjacent unused spots          if (grid[location] == 0) {                    // if not already used             coords[x++] = location;                    // save location             location += incr;                          // try 'next' adjacent             if (location >= gridSize){                 // out of bounds - 'bottom'               success = false;                         // failure             }             if (x>0 & (location % gridLength == 0)) {  // out of bounds - right edge               success = false;                         // failure             }          } else {                                      // found already used location              // System.out.print(" used " + location);                success = false;                          // failure          }        }    }                                                   // end while    int x = 0;                                          // turn good location into alpha coords    int row = 0;    int column = 0;    // System.out.println("\n");    while (x < comSize) {      grid[coords[x]] = 1;                              // mark master grid pts. as 'used'      row = (int) (coords[x] / gridLength);             // get row value      column = coords[x] % gridLength;                  // get numeric column value      temp = String.valueOf(alphabet.charAt(column));   // convert to alpha      alphaCells.add(temp.concat(Integer.toString(row)));      x++;      // System.out.print("  coord "+x+" = " + alphaCells.get(x-1));    }    // System.out.println("\n");    return alphaCells;   }}

结果为该次改动能够实现输入的读取，进行互动化；
然而存在不足，为当命中目标后再次猜测统一坐标仍然有效，需要再改。

3.0