我試圖在java中重新創建一個打印機,我是相當新的編程,所以我在單個函數內部使用巨大的if else塊來指示程序的邏輯,我注意到這是在同一個函數內部創建了大量的代碼,我想知道是否有一個更有說服力的/有效的方法來做到這一點,下面的打印機類。打印機的邏輯並不太重要,但無論如何,只是一個不是雙面打印機,邏輯負責檢查墨粉量,確保打印的頁面與雙面打印機一致或不。如果其他語句更有效
package com.company;
public class Printer {
private String name;
private double tonerLevel = 100;
private int ammountOfPaper;
private int numberOfPagesPrinted;
private boolean isDoubleSided;
public Printer(String name, double tonerLevel, int ammountOfPaper, boolean isDoubleSided) {
this.name = name;
if(tonerLevel >= 0 && tonerLevel <= 100) {
this.tonerLevel = tonerLevel;
}
this.ammountOfPaper = ammountOfPaper;
this.isDoubleSided = isDoubleSided;
}
private boolean isOutOfToner(double numberToPrint) {
if((tonerLevel - (numberToPrint/2) < 0)) {
return true;
}
else {
return false;
}
}
private boolean isOutOfPaper(double numberToPrint) {
if(((ammountOfPaper - numberToPrint) < 0)) {
return true;
}
else {
return false;
}
}
private boolean twoSideNoPaperEven(double numberToPrint) {
if((ammountOfPaper - ((int) numberToPrint/2)) < 0) {
return true;
}
else {
return false;
}
}
private boolean twoSideNoPaperOdd(double numberToPrint) {
if(((ammountOfPaper - ((int) numberToPrint/2)) - 1) < 0) {
return true;
}
else {
return false;
}
}
public void printPages(double numberToPrint) {
if(isDoubleSided == false) {
if(tonerLevel == 0) {
System.out.println("Out of toner");
}
if(ammountOfPaper == 0) {
System.out.println("Out of Paper");
}
if(isOutOfToner(numberToPrint) && (tonerLevel != 0)) {
double difference = tonerLevel * 2;
numberToPrint = difference;
ammountOfPaper -= numberToPrint;
System.out.println("Will run out of toner after this print, able to print " + (int) numberToPrint +
" pages");
tonerLevel = 0;
}
if(isOutOfPaper(numberToPrint) && (ammountOfPaper != 0)) {
double different = ammountOfPaper - numberToPrint;
numberToPrint = numberToPrint + different;
System.out.println("Will run out of paper after this print, printing " + (int) numberToPrint + " pages");
ammountOfPaper = 0;
}
else if(!isOutOfToner(numberToPrint) && (!isOutOfPaper(numberToPrint))) {
ammountOfPaper -= numberToPrint;
tonerLevel = tonerLevel - (numberToPrint/2);
showPages(numberToPrint);
}
}
else if(isDoubleSided = true) {
if (numberToPrint % 2 == 0) {
if(tonerLevel == 0) {
System.out.println("Out of Toner");
}
if(ammountOfPaper == 0) {
System.out.println("Out of Paper");
}
if(twoSideNoPaperEven(numberToPrint) && (ammountOfPaper != 0)) {
ammountOfPaper -= numberToPrint/2;
System.out.println("There is no Paper");
}
else if(!twoSideNoPaperEven(numberToPrint)) {
tonerLevel = tonerLevel - (numberToPrint/2);
ammountOfPaper -= numberToPrint/2;
showPages(numberToPrint);
}
} else {
if(tonerLevel == 0) {
System.out.println("Out of Toner");
}
if(ammountOfPaper == 0) {
System.out.println("Out of Paper");
}
if(twoSideNoPaperOdd(numberToPrint) && (ammountOfPaper != 0)) {
System.out.println("There is no paper");
ammountOfPaper = (ammountOfPaper - ((int) numberToPrint/2)) - 1;
ammountOfPaper = 0;
}
else if(!twoSideNoPaperOdd(numberToPrint)) {
tonerLevel = tonerLevel - (numberToPrint/2);
ammountOfPaper = (ammountOfPaper - ((int) numberToPrint/2)) - 1;
showPages(numberToPrint);
}
}
}
}
public void showPages(double numberToPrint) {
System.out.println("Printing " + (int) numberToPrint + " Pages, paper remaining is: " + this.ammountOfPaper
+ " Toner level is: " + this.tonerLevel);
}
public void refillToner() {
tonerLevel = 100;
}
public void refillPaper(int paper) {
if(paper > 50) {
System.out.println("Cannot put in more paper");
}
else {
this.ammountOfPaper += paper;
}
}
public int getAmmountOfPaper() {
return ammountOfPaper;
}
public double getTonerLevel() {
return tonerLevel;
}
public void setTonerLevel(double tonerLevel) {
this.tonerLevel = tonerLevel;
}
public void setAmmountOfPaper(int ammountOfPaper) {
this.ammountOfPaper = ammountOfPaper;
}
更改if語句由Nicolas的建議:
public void printPages(double numberToPrint) {
if(tonerLevel == 0) {
System.out.println("Out of toner");
return;
}
if(ammountOfPaper == 0) {
System.out.println("Out of Paper");
return;
}
if(isDoubleSided == false) {
'if'陳述評價布爾值不管怎麼說,有一個在做'如果(somecondition)返回true,否則返回FALSE',你可以只是做回'沒有somecondition'點。但這並沒有多少效率,它只是消除了幾行冗餘代碼。 –
儘早使用,即'if(tonerLevel == 0){System.out。 ...;返回; }'等等。因此你不必一次又一次檢查。還可以嘗試將不同的分支分解爲不同的方法或類(例如,子類或策略模式),如單面或雙面。 – Thomas
我正在投票結束這個問題,因爲它已被交叉發佈在更適合的Stack Exchange站點上。將來,請僅在單個Stack Exchange站點上發佈您的問題。有關更多信息,請參閱[這裏](http://meta.stackexchange.com/q/64068)。 (http://codereview.stackexchange.com/questions/138774/simulating-a-printer)。 – Matt