Java中如何使字符型的数字变成整型

Question

有种方法:String str = "45642315";
int i =Integer.parseInt(str.charAt(0).toString())
太过去麻烦了，有没有简单点的方法 .

Answer 1

public class JJArrangedNumbers1 {
public static void main(String args[]) {
Scanner scanner = new Scanner(System.in);
while (true) {
String line;
System.out.println("请任意输入数字，以空格间隔，以回车结束！");
line = scanner.nextLine();
ArrangedNumbers arrangeNumbers = new ArrangedNumbers();
if (arrangeNumbers.isNumbers(line)) {
String[] stringNumbers = arrangeNumbers.deleteSpaces(line);
int[] arrayNumbers = Integer.parseInt(stringNumbers);
arrangeNumbers.compareNumbers(arrayNumbers);
arrangeNumbers.outputNumbers(arrayNumbers);
}
String space=" ";
if (line.endsWith(space))
return;
}
}
}
错误: int[] arrayNumbers = Integer.parseInt(stringNumbers); 找不到符号?

补充：import java.util.Scanner;
public class zeng
{
public static void main(String args[])
{
Scanner scanner = new Scanner(System.in);
String numbers;
System.out.println("请任意输入数字，以整型输出");
numbers = scanner.nextLine();
ArrangedNumbers arrangeNumbers = new ArrangedNumbers();
int[] arrayNumbers = arrangeNumbers.getNumbers(numbers);
System.out.println("按int类型输出：");
for (int i=0;i<arrayNumbers.length;i++)
{
System.out.println("arrayNumbers[" + i + "]=" + arrayNumbers[i]);
}
}
}
class ArrangedNumbers
{
public int[] getNumbers(String numbers)
{
/*
数组中的整数总数
*/
int count = 0;
int integerNumbers;
for (int i=0;i<numbers.length();i++)
{
int memoryNumbers;
memoryNumbers=Integer.parseInt(numbers);
integerNumbers[count++] = new Integer(memoryNumbers).intValue();
}
return integerNumbers;
}
}

Answer 2

String str = "45642315";
int i =str.charAt(0).intvalue();

Answer 3

int intvalue=Integer.parseInt(intString)
你看这行不？

Answer 4

补充下：其中intString是一个数值型字符串，如你的“45642315”