我正在尝试制作一个允许用户将犯罪输入“犯罪数据库”的小方法,它只会显示犯下此罪行的罪犯。
不幸的是,我必须使用2D数组。我写了一个方法,但它没有给我我正在寻找的输出。
以下是方法:
//method to search data
public static void searchData() throws IOException{
int flag = 0;
boolean found = false;
//input search key
System.out.print("Which crime would you like to select? (arson, theft, assault) ");
String searchKey = br.readLine();
System.out.println("You searched for criminals with the offence of \"" + searchKey + "\".");
System.out.println("Name - Crime - Year of Conviction");
for(int i = 0; i < criminals.length; i++){
if(searchKey.compareTo(criminals[i][1]) == 0){
flag = i;
found = true;
}
}
if(found == false){
System.out.println("Error! Crime not found.");
}else{
System.out.println("Criminals found.");
for(int i = 0; i < criminals.length; i++){
System.out.println(criminals[flag][0] + " - " + criminals[flag][1] + " - " + criminals[flag][2]);
}
}
}
我的意见是:
George - theft - 1999
Eddie - assault - 2003
Al - theft - 1999
以下是测试后的输出:
Which crime would you like to select? (arson, theft, assault) theft
You searched for criminals with the offence of "theft".
Criminals found.
Al - theft - 1999
Al - theft - 1999
Al - theft - 1999
你能帮我弄清楚这有什么问题吗?提前致谢。 :)
答案 0 :(得分:1)
你一直在打印最后被发现的罪犯(旗帜)。
for(int i = 0; i < criminals.length; i++){
if(searchKey.compareTo(criminals[i][1]) == 0){
if(!found) {
found = true;
System.out.println("Criminals found.");
}
System.out.println(criminals[i][0] + " - " + criminals[i][1] + " - " + criminals[i][2]);
}
}
if(found == false){
System.out.println("Error! Crime not found.");
}
答案 1 :(得分:1)
只是增加代码重用和可维护性(如果需要)的一些小增加:
for
循环代替显式元素寻址:What is the syntax of enhanced for loop in Java? false
进行比较,您可能希望使用!
运算符来使代码更具可读性.equals
比.compareTo .. == 0
更清晰(至少在这种情况下)