请完善程序(程序文件名：Java_3.java)并进行调试。请在下画线处填入正确内容，然后删除下画线。请勿删除注释行和其他已有的语句内容。
[题目要求]
统计一个英文文本字符串包含的英文元音字母的个数，使程序的运行结果如下：
The text contained vowels:88
源程序：
public class Java_3 {
public static void main(String[] args) {
String text = " Beijing, the Capital City, is the political, "
+ "cultural and diplomatic centre of China. It has"
+ "become a modern international cosmopolitan city"
+ " with more than 11 million people. The Capital"
+ " International Airport, 23.5 km from the city centre,"
+ "is China's largest and most advanced airport. " ;
int vowels =0;
int {{U}}(1) {{/U}}= text.length();
for(int i = 0;i＜textLength; i++) {
char ch=Character.toLowerCase( text.{{U}} (2) {{/U}});
if(ch=='a'||ch=='e'||ch=='i'||ch=='o'||ch=='u')
{{U}} (3) {{/U}};
}
System.out.println( "The text contained vowels:" + vowels +"/n");
}
}