如何测试字符串数组以查找特定字符串是否在数组中？

Question

I have this part of my code so far. It compiles fine and runs fine. But If I choose to insert a Rank that isn't in the list it still prints the value that I input.

private String         Rank;  //string r
private static String[] Ranks = {"Assistant", "Associate", "Full"};

public professor(String n, int a, int s, String r, int nc, int pp)
{
    super(n, a, s);
    setRank(r);
    setNumCo(nc);
    setPubPaps(pp);
}
//mutator to set the Rank and check to make sure it is in the string list
public void setRank(String r)
{
    boolean check = false;

    List valid = Arrays.asList(this.Ranks);

    if(valid.contains(r)) 
        check = true;

    if(check = true)
        this.Rank = r;
    else
        this.Rank = "Associate";
}

Here's an example of what I'm talking about:

 professor p2 = new professor ("Muench", 50, 222344455, "False", 3, 45);

"False" is definitely not in the list of ranks but it will still print as follows in my print window False professor Muench....

Answer 1

writing it like this will work and a lot more readable

List valid = Arrays.asList(this.Ranks);

if(valid.contains(r)) 
    this.Rank = r;
else
    this.Rank = "Associate";

This works because the .contains method returns a boolean value so you basically end up with if(true) or if(false) when the value is returned

Answer 2

if(valid.contains(r)) 
        check = true;

    if(check == true)
        this.Rank = r;
    else
        this.Rank = "Associate";

Answer 3

You can also do it using your array of strings (without converting the array to a list):

public void setRank(String r)
{
  for ( final String rank : professor.Ranks ) // Static reference to Ranks class variable.
  {
    if ( rank.equals( r ) )
    {
      this.Rank = r;
      return;
    }
  }
  this.Rank = "Associate";
}

You also have an odd naming convention:

• the class professor is entirely in lower case when it is usual to capitalise (or camel-case) class names.
• the attribute Rank is capitolised when the normal convention is to use lower case.

Answer 4

Using Java 8

If case sensitive

public void setRank(String r){
       this.Rank = Stream.of(Ranks).filter(p->p.equals(r)).findAny().orElse("Associate");
}

If not case sensitive

public void setRank(String r){
       this.Rank = Stream.of(Ranks).filter(p->p.equalsIgnoreCase(r)).findAny().orElse("Associate");
}