1
我不知道這個錯誤是什麼或爲什麼發生。我在網上發現的東西與TableViews無關。但是當我的囚犯類中的這個方法被我的TableView訪問時,它會拋出一個InvocationTargetException
。這是我第一次使用TableView。Java InvocationTargetException當填充TableView
public int getCellBlock() {
for (int i = 0; i < Main.getCellBlocks().size(); i++) //for each cellblock
for (int j = 0; j < Main.getCellBlocks().get(i).getCells().size(); j++) //for each cell
for (int k = 0; k < Main.getCellBlocks().get(i).getCells().get(j).getInmates().size(); k++)
if (Main.getCellBlocks().get(i).getCells().get(j).getInmates().get(k).equals(this.idNum)) {
return i;
}
return -1;
}
細胞(有兩個子類,但即時通訊不訪問在其中數據用上述方法):
import java.io.Serializable;
import java.util.ArrayList;
public class Cell implements Serializable {
private ArrayList<Integer> inmateIdNums;
private int capacity = 0;
Cell(int cap){
capacity = cap;
inmateIdNums = new ArrayList<>();
for (int i = 0; i < capacity; i++)
inmateIdNums.add(null);
}
public void add (int idNum){
for (int i = 0; i < capacity; i++){
if (inmateIdNums.get(i) == null) {
inmateIdNums.set(i, idNum);
break;
}
}
}
public void add (int idNum, int dur){}
public void add (int idNum, String reason){}
public ArrayList<Integer> getInmates(){ return inmateIdNums; }
public int getEmptyBunks(){
int emptyBunks = 0;
for (int i = 0; i < inmateIdNums.size(); i++){
if (inmateIdNums.get(i) == null)
emptyBunks++;
}
return emptyBunks;
}
}
監獄分區:
import java.io.Serializable;
import java.util.ArrayList;
public class CellBlock implements Serializable{
private String name;
private String type;
private int capacity;
private int occupancy = 0;
private ArrayList<Cell> cells;
CellBlock(int cap, String nName, String nType, int cellCapacity){
name = nName;
type = nType;
capacity = cap;
cells = new ArrayList<>(capacity);
if (type == "Maximum Security" || type == "Minimum Security") {
for (int i = 0; i < capacity; i++)
cells.add(new Cell(cellCapacity));
}
else if(type == "Infirmary"){
for (int i = 0; i < capacity; i++)
cells.add(new InfirmaryCell(cellCapacity));
}
else if(type == "Isolation"){
for (int i = 0; i < capacity; i++)
cells.add(new IsolationCell(cellCapacity));
}
}
public void addInmate(int cell, int inmateIdNum){
cells.get(cell-1).add(inmateIdNum);
occupancy++;
}
public void addInmate(int cell, int inmateIdNum, String reason){
cells.get(cell-1).add(inmateIdNum, reason);
occupancy++;
}
public void addInmate(int cell, int inmateIdNum, int duration){
cells.get(cell-1).add(inmateIdNum, duration);
occupancy++;
}
public void removeInmate(int inmateIdNum){
//search for inmate and remove from list
}
public ArrayList<Cell> getInmates(){ return cells; }
public boolean checkCapacity(){
if (capacity > occupancy)
return true;
return false;
}
public ArrayList<Cell> getCells(){ return cells; }
public ArrayList<String> getOpenCells(){
ArrayList<String> openCells = new ArrayList<>();
for (int i = 0; i < cells.size();i++){
if (cells.get(i).getEmptyBunks() > 0)
openCells.add(Integer.toString(i+1));
}
return openCells;
}
}
的錯誤:
原因是Prisoner.java第68行有一個'NullPointerException'。 (你應該在問題中指出哪一行是第68行。)這意味着你正在調用一個'null'引用的方法。既然你的代碼把方法調用的長序列鏈接在一起,你可能不得不解開那些來弄清楚什麼是空的。 –
請不要張貼堆棧跟蹤的截圖,而是將堆棧跟蹤文本複製並粘貼到您的問題中。 – jewelsea
@jewelsea我打算這樣做,但是這麼長(比圖像中的東西還要長),我無法用任何方式來格式化所有那些容易在眼睛上看到的東西。 – Alyssa