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“找不到符号”或“无法解析符号”错误是什么意思(（17个答案）
昨天关门了。
这是我正在处理数据结构的类的代码。现在我们正试图和max heap合作，我想我遇到了麻烦。当我尝试在jgrasp中编译这些数据时，我在build方法周围得到了一个“java:82错误：找不到符号”，特别是“data.insert（arr[z]）；”它说找不到insert方法。
通常，当我遇到这个错误时，我认为是拼写或大小写错误，但经过四重检查，我肯定不是这样。在build方法之外运行insert方法似乎很好，只是我似乎无法在任何其他方法中运行insert方法。我觉得我在这里犯了一个明显的错误，但我无法确定。

import java.util.*;

class HeapMax {
    // we go with arraylist instead of array for size flexibility
    private ArrayList<Integer> data;
    int Size;
    // default constructor
    public HeapMax() {
      data = new ArrayList<Integer>(0);
      //adding an integer to the dataset just makes it so that I can work from position 1 rather than 0
      //I think this is somewhat easier for the math that needs to be done
      //being max value ensures it is always at the front and doesn't accidentally get sorted, like a 0 would
      data.add(Integer.MAX_VALUE);
      //size variable for future reference
      Size = 0;
    }

    // DO NOT MODIFY THIS METHOD
    public ArrayList<Integer> getData() {
      return data;
    }

    // insert a new element and restore max heap property
    public void insert(int element) {
         data.add(element);
         //increases size for future reference
         Size++;
         int CurrentSize = Size;
         //organizes leaves in accordance with their parents
         while(data.get(CurrentSize) > data.get(CurrentSize/2)){
            int reserveInt = data.get(CurrentSize);
            data.set(CurrentSize, data.get(CurrentSize/2));
            data.set(CurrentSize/2, reserveInt);   
            CurrentSize = (CurrentSize/2);   
         }
   }     

    // return max
    public int getMax() {
      // remove this line
      return 0;
    }

    // remove max and restore max heap property
    public int removeMax() {

      return 0;
    }

    // print out heap as instructed in the handout
    public void display() {
         System.out.print("Current heap is: ");
         int currentTierSize = 1;
         int currentSpot = 1;
         //iterates over the array, printing everything but the very last tier
         //this is because the final tier is not necessarily full, and continuing would result in null pointer exception
         while (currentSpot < (Size-1)){
            for(int i = 0; i < currentTierSize; i++){
               System.out.print(data.get(currentSpot)+ " ");
               currentSpot++;
            }
            System.out.print(",");
            //tiers are in iterations of two, so the next will always be twice as large as the last
            currentTierSize = currentTierSize * 2;          
         }
         //the size of the final tier will always be determinable by the differce between the place the previous iteration left off and the size of the full array
         //this iterates over those spaces, finishing the display without an exception
         int finalTierSize = (Size - (currentSpot-1));
         for(int j = 0; j < finalTierSize; j++){
            System.out.print(data.get(currentSpot) + " ");
            currentSpot++;
         }
         System.out.println(".");

    }
        // heap builder
    public void build(int[] arr) {
         for(int z = 0; z < arr.length; z++){
            data.insert(arr[z]);
         }
    }

    // you are welcome to add any supporting methods
    public static void main(String[] args){
          HeapMax data = new HeapMax();
          int[] testArray = {5,3,17,10,84,19,6,22,9};

          data.build(testArray);
          data.display();

    }
}