Question

我想知道是否有类test1的两个数组testSet和testSet2 在方法问题（）中，testSet初始化为1，testSet2初始化为0 在使用testSet对testSet2进行均衡后，testSet2长度与testSet相同，这很好但在方法problem1（）中，testSet初始化为1，testSet2初始化为0 并且在方法equize（）中均衡后，testSet2与testSet的testSet2长度变为0。为什么呢？

public class test1
{
    // C
    public test1(int _data)
    {
        data = _data;
    }

    // Field
    public int data;
}

// reference equalize method
public void equalize(test1[] a,test1[] b)
{
    a = b;
}

public test1[] testSet,testSet2; // arrays

// called from main method access
public void Problem()
{    
    // initializing array
    testSet = new test1[1];
    testSet2 = new test1[0];

    testSet [0] = new test1 (11);
    testSet2 = testSet;  

    // testSet2.length = 1 which is fine
}

// called from main method access
public void Problem1()
{  
    testSet = new test1[1];
    testSet2 = new test1[0];

    testSet [0] = new test1 (11);
    equalize (testSet2,testSet);

    // want to know why this is happening ?
    // testSet2.length = 0 
    // in problem() length = 1 but here is 0 why?
}

Answer 1

testSet2 = 0的原因是因为方法equalize（）只在里面使用它们。 methods（）仅代表他们使用参数。

如果要更改testSet2的长度。

启动它

  public TestClass(int _data)
   {
        data = _data;
    testSet2 = new TestClass[0];
}

 and when you want to change it's length try this

 public void Problem1()
{  
testSet = new TestClass[1];
testSet [0] = new TestClass (11);
 equalize (testSet);   

System.out.println(testSet2.length);
System.out.println(testSet.length);



 }

  public void equalize(TestClass[] b)
{
testSet2 = b;
 }

java方法中的1D数组设置

1 个答案: