我是 Java Eclipse 的初学者。我正在尝试读取 .txt 文件，并将数据用作字符串值。但是，当我使用if语句时，条件没有将值注册为字符串，因此不满足任何条件，我只得到最终的else.
我的代码的目的是读取文本文件并确定所需的值：即如果行以 "avg" 开头，则程序必须显示以下数字的平均值。
我的 .txt 文件内容是这样的：
最小值:1,2,3,4,5,6\n 最大值:1,2,3,4,5,6\n 平均值:1,2,3,4,5,6
这是我的代码的一部分：
public static void main(String[] args) throws IOException {
//declare variables
String line, operation;
int min, max, sum, num;
double avg;
List<String> lineArray;
String outputPath = "C:\\output.txt"; //these are not the actual file paths, i just didnt
String inputPath = "C:\\input.txt"; //want to give personal information.
//try open file
try {
//create File instance
File text = new File (inputPath);
Scanner scnr = new Scanner(text);
//loop until end of text file
while ( scnr.hasNextLine() ) {
line = scnr.nextLine(); //read line from text file
operation = line.substring(0,3); //get operation from String data
line = line.substring(4); //get String value of numbers
lineArray = Arrays.asList(line.split(",")); //separate string into array elements
//setup initial values
sum = 0;
min = Integer.parseInt(lineArray.get(0)); //convert to Int
max = Integer.parseInt(lineArray.get(0));
//loop through line array and determine min, sum and max of each
for (int i = 0; i < lineArray.size(); i++ ) {
num = Integer.parseInt(lineArray.get(i));
sum += Integer.parseInt(lineArray.get(i));
if (num > max) max = num;
if (num < max) max = num;
}
avg = sum / lineArray.size();
//the IF condition statement that is not working
if (operation == "min") {
System.out.println(min);
}
else if (operation == "max") {
System.out.println(max);
}
else if (operation == "avg") {
System.out.println(avg);
}
else System.out.println("Error");
} //end of while loop
scnr.close(); //close scanner
} //end of try
catch ( FileNotFoundException e ) {
}
} //end of "main" class
当我手动将操作设置为“min”或“max”或“avg”时，程序会正常工作。