if语句Java，方法从if/else打印两个选项

Question

嗨，这是我为一个项目编写的一些代码，它调用了其他几个方法来打印关于此人的声明。我的问题是它以双精度打印，并且似乎正在运行if/else语句

我怎样才能防止这种情况？如果需要，我可以从终端添加文本。代码如下

 void printPersonDescription(String name, boolean sex, int age) {

    if(sex == true && yearsUntilNextMaturityLevel(age) > 1) {
        println (name + " is " + getMaturityLevel(age) + ". " + "At " + age + 
        " she has " + yearsUntilNextMaturityLevel(age) + " years left until she is " + 
        nextMaturityLevel(age) + "."); 
    }
    else if(sex == false && yearsUntilNextMaturityLevel(age) > 1) {
        println (name + " is " + getMaturityLevel(age) + ". " + "At " + age + 
        " he has " + yearsUntilNextMaturityLevel(age) + " years left until he is " + 
        nextMaturityLevel(age) + ".");
    }
    if (sex == true && yearsUntilNextMaturityLevel(age) <= 1) {
        println (name + " is " + getMaturityLevel(age) + ". " + "At " + age + 
        " she has " + yearsUntilNextMaturityLevel(age) + " year left until she is " + 
        nextMaturityLevel(age) + "."); 
    }
    else {
        println (name + " is " + getMaturityLevel(age) + ". " + "At " + age + 
        " he has " + yearsUntilNextMaturityLevel(age) + " year left until he is " + 
        nextMaturityLevel(age) + ".");
    }

}

Answer 1

注意你的四个案例有多相似。你只是在修改打印行中的一些单词。这四个if/else块可以简化为：

void printPersonDescription(String name, boolean sex, int age) {
    int years = yearsUntilNextMaturityLevel(age);
    String gender = sex ? "she" : "he";
    String plural = years > 1 ? "s" : "";
    println(name + " is " + getMaturityLevel(age) + ". " + "At " + age + 
    " " + gender + " has " + years + " year" + plural + " left until " + gender + " is " + 
    nextMaturityLevel(age) + "."); 
}

此外，通过使用String.format（假设成熟度级别是字符串），可以使println更具可读性

String.format("%s is %s. At %d %s has %d year%s left until %s is %s.", 
        name, getMaturityLevel(age), age, gender, years, plural, gender, 
        nextMaturityLevel(age))

Answer 2

 void printPersonDescription(String name, boolean sex, int age) {

    if(sex == true && yearsUntilNextMaturityLevel(age) > 1) {
        println (name + " is " + getMaturityLevel(age) + ". " + "At " + age + 
        " she has " + yearsUntilNextMaturityLevel(age) + " years left until she is " + 
        nextMaturityLevel(age) + "."); 
    }
    else if(sex == false && yearsUntilNextMaturityLevel(age) > 1) {
        println (name + " is " + getMaturityLevel(age) + ". " + "At " + age + 
        " he has " + yearsUntilNextMaturityLevel(age) + " years left until he is " + 
        nextMaturityLevel(age) + ".");
    }
    else if (sex == true && yearsUntilNextMaturityLevel(age) <= 1) {    
        println (name + " is " + getMaturityLevel(age) + ". " + "At " + age + 
        " she has " + yearsUntilNextMaturityLevel(age) + " year left until she is " + 
        nextMaturityLevel(age) + "."); 
    }
    else {
        println (name + " is " + getMaturityLevel(age) + ". " + "At " + age + 
        " he has " + yearsUntilNextMaturityLevel(age) + " year left until he is " + 
        nextMaturityLevel(age) + ".");
    }

}

您需要在第三个if之前添加else。否则，最后的else语句将匹配第三个if，因此，else语句意味着

if(sex != true || yearsUntilNextMaturityLevel(age) > 1)

Answer 3

第三个if条件应该是代码中的else if，以避免重复打印

而不是：

if (sex == true && yearsUntilNextMaturityLevel(age) <= 1) {

使用：

else if (sex && yearsUntilNextMaturityLevel(age) <= 1) {

顺便说一句，你不需要使用if (boolVar == true)你只需要使用if (boolVar)