訪問類數據

Question

我想訪問我使用結構創建的數據，但我似乎無法弄清楚如何。在我的課上，我有3個變量。

public class Data 
{ 
    private double tempCelc; 
    private double tempKelv; 
    private double tempFahr; 
} 

我也有創建此類

Data(final double tempCelcius) 
{ 
    this.tempCelc = tempCelcius; 
    this.tempFahr = this.celToFar(tempCelcius); 
    this.tempKelv = this.celToKel(tempCelcius); 
} 

的7個實例構造函數我不知道怎麼我能得到有關訪問的具體tempFahr或tempKelv爲類的特定實例。這是我的循環使用的構造：

for(int i = 0; i < temperatures.length; i++) 
    { 
     System.out.println("Please enter the temperature in Celcius for day " + (i+1)); 
     temperatures[i] = new Data(input.nextDouble()); 
    } 

Answer 1

創建getter和setter方法對數據

public class Data 
{ 
    private double tempCelc; 
    private double tempKelv; 
    private double tempFahr; 

    Data(final double tempCelcius) 
    { 
     this.tempCelc = tempCelcius; 
     this.tempFahr = this.celToFar(tempCelcius); 
     this.tempKelv = this.celToKel(tempCelcius); 
    } 

    //getter example 
    public double getTempFahr() 
    { 
     return this.tempFahr; 
    } 
    //setter example 
    public void setTempFahr(double tempFahr) 
    { 
     this.tempFahr = tempFahr; 
    } 
    //add other getter and setters here 
} 

等等

訪問，如：

temperatures[0].getTempFahr(); 
temperatures[0].setTempFahr(80.5); 

Answer 2

你的模型班應該看起來像這樣：

public class Data{ 

private double tempCelc; 
private double tempKelv; 
private double tempFahr; 

// constructor method 
Data(final double tempCelcius) 
{ 
    this.tempCelc = tempCelcius; 
    this.tempFahr = this.celToFar(tempCelcius); 
    this.tempKelv = this.celToKel(tempCelcius); 
} 
// Accessor methods implementation 
public double getTempCelc(){ 
    return this.tempCelc; 
} 


public double getTempKelv(){ 
    return this.tempKelv; 
} 


public double getTempFahr(){ 
    return this.tempFahr; 
}  

}

進出類，例如的你的主要方法創建對象：

for(int i = 0; i < 10; i++) 
    { 
     System.out.println("Please enter the temperature in Celcius for day " + (i+1)); 
     temperatures[i] = new Data(input.nextDouble()); 
    } 

然後你訪問它們：

for(int i = 0; i < temperatures.length; i++){ 

    System.out.println("i : " + i + " cecl : " + temperatures[i].getCelc() + " kelvin : " + temperatures[i].getTempKelv() + " fahr : " + temperatures[i].getFahr()); 

}