将数组排序为三个不同的ArrayLinearLists

尝试将.txt文件中的数据排序为三个不同的ArrayLinearLists。但是问题在于他们的容量。每当调用.add函数时，容量都会增加一倍。

public static void main(String[] args) throws IOException { // TODO Auto-generated method stub String line; int indexOfCode = 0; int indexOfName = 1; int indexOfCredit = 2; int count = 0; ArrayLinearList codeR = new ArrayLinearList(); ArrayLinearList nameR = new ArrayLinearList(); ArrayLinearList creditR = new ArrayLinearList(); try (BufferedReader br = new BufferedReader(new FileReader("Subjects.txt"))) {

    while ((line = br.readLine()) != null) {
        String values[] = line.split("/");
        codeR.add(0, values[indexOfCode]);
        nameR.add(0, values[indexOfName]);
        creditR.add(0, values[indexOfCredit]);
    }

    System.out.println(codeR);
    System.out.println(nameR);
    System.out.println(creditR);

}

} 这是ArrayLinearList代码

protected Object[] element; // array of elements protected static int size; // number of elements in array protected static ArrayLinearList theObject;

// constructors /** * create a list with initial capacity initialCapacity * * @throws IllegalArgumentException * when initialCapacity < 1 */ public ArrayLinearList(int initialCapacity) { if (initialCapacity < 1) throw new IllegalArgumentException("initialCapacity must be >= 1"); // size has the default initial value of 0 element = new Object[initialCapacity]; }

/** create a list with initial capacity 10 */ public ArrayLinearList() {// use default capacity of 10 this(10); }

// methods /** @return true iff list is empty */ public boolean isEmpty() { return size == 0; }

/** @return current number of elements in list */ public int size() { return size; }

/** * @throws IndexOutOfBoundsException * when index is not between 0 and size - 1 */ void checkIndex(int index) { if (index < 0 || index >= size) throw new IndexOutOfBoundsException("index = " + index + " size = " + size); }

/** * @return element with specified index * @throws IndexOutOfBoundsException * when index is not between 0 and size - 1 */ public Object get(int index) { checkIndex(index); return element[index]; }

/** * @return index of first occurrence of theElement, return -1 if theElement * not in list */ public int indexOf(Object theElement) { // search element[] for theElement for (int i = 0; i < size; i++) if (element[i].equals(theElement)) return i;

// theElement not found
return -1;

}

/** * Remove the element with specified index. All elements with higher index * have their index reduced by 1. * * @throws IndexOutOfBoundsException * when index is not between 0 and size - 1 * @return removed element */ public Object remove(int index) { checkIndex(index);

// valid index, shift elements with higher index
Object removedElement = element[index];
for (int i = index + 1; i < size; i++)
    element[i - 1] = element[i];

element[--size] = null; // enable garbage collection
return removedElement;

}

/** * Insert an element with specified index. All elements with equal or higher * index have their index increased by 1. * * @throws IndexOutOfBoundsException * when index is not between 0 and size */ public void add(int index, Object theElement) { if (index < 0 || index > size) // invalid list position throw new IndexOutOfBoundsException("index = " + index + " size = " + size);

// valid index, make sure we have space
if (size == element.length)
    // no space, double capacity
    element = ChangeArrayLength.changeLength1D(element,2* size);

// shift elements right one position
for (int i = size - 1; i >= index; i--)
    element[i + 1] = element[i];

element[index] = theElement;

size++;

}

/** convert to a string */ public String toString() { StringBuffer s = new StringBuffer("[");

// put elements into the buffer
for (int i = 0; i < size; i++)
    if (element[i] == null)
        s.append("null, ");
    else
        s.append(element[i].toString() + ", ");

if (size > 0)
    s.delete(s.length() - 2, s.length()); // remove last ", "

s.append("]");

// create equivalent String
return new String(s);

}

/** create and return an iterator */ public Iterator iterator() { return new ArrayLinearListIterator((MyArrayList) this); }

/** test program */ public static void main(String[] args) { // test default constructor LinearList x = new ArrayLinearList();

// test size
System.out.println("Initial size is " + x.size());

// test isEmpty
if (x.isEmpty())
    System.out.println("The list is empty");
else
    System.out.println("The list is not empty");

// test put
x.add(0, new Integer(2));
x.add(1, new Integer(6));
x.add(0, new Integer(1));
x.add(2, new Integer(4));
System.out.println("List size is " + x.size());

// test toString
System.out.println("The list is " + x);

// test indexOf
int index = x.indexOf(new Integer(4));
if (index < 0)
    System.out.println("4 not found");
else
    System.out.println("The index of 4 is " + index);

index = x.indexOf(new Integer(3));
if (index < 0)
    System.out.println("3 not found");
else
    System.out.println("The index of 3 is " + index);

// test get
System.out.println("Element at 0 is " + x.get(0));
System.out.println("Element at 3 is " + x.get(3));

// test remove
System.out.println(x.remove(1) + " removed");
System.out.println("The list is " + x);
System.out.println(x.remove(2) + " removed");
System.out.println("The list is " + x);

if (x.isEmpty())
    System.out.println("The list is empty");
else
    System.out.println("The list is not empty");

System.out.println("List size is " + x.size());

}