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String literal with toCharArray() producing garbage in Java

I wanted to create a char array of the alphabet. I looked at this post:
Better way to generate array of all letters in the alphabet
which said this:
char[] alphabet = "abcdefghijklmnopqrstuvwxyz".toCharArray();
So in my code I have:
public class Alphabet {
private char[] letters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();
public String availableLetters(){
return letters.toString();
}
}
When I call the function availableLetters() from main() and printit to the console, it outputs this garbage:
[C#15db9742
What am I doing wrong?

The array is correct, the problem is that you are not printing it correctly.
If you print your array one character at a time, you would get a correct result:
for (char c : letters) {
System.out.print("'" + c + "' ");
}
demo
Unfortunately, Java standard class library does not provide a meaningful override of toString() for arrays, causing a lot of trouble for programmers who are new to the language.

If you want to print it in array form, then use:
System.out.println(Arrays.toString(letters));
BTW: The [C#15db9742 is not really garbage. It's what gets printed out when a class does not override the toString() method.
From Object.toString():
Returns a string representation of the object. In general, the
toString method returns a string that "textually represents" this
object. The result should be a concise but informative representation
that is easy for a person to read. It is recommended that all
subclasses override this method. The toString method for class Object
returns a string consisting of the name of the class of which the
object is an instance, the at-sign character `#', and the unsigned
hexadecimal representation of the hash code of the object. In other
words, this method returns a string equal to the value of:
getClass().getName() + '#' + Integer.toHexString(hashCode())

You can pass the char array to the String constructor or the static method String.valueOf() and return that instead.

Java toString method in char[] [duplicate]

This question already has answers here:
Why does the toString method in java not seem to work for an array
(9 answers)
How to convert a char array back to a string?
(14 answers)
Closed 9 years ago.
I thought the toString method will make a char array to a String, but I was wrong.
char[] k=new char[2];
k[0]='k';
k[1]='k';
System.out.println(k.toString());
This code will output: [C#112f614.
What exactly happened in this code k.toString()?
Should I never call toString method in a char array?
Thanks!
Happy New Year!

You want to use Arrays.toString(char[]{'a','b'});
You can use
char data[] = {'a', 'b', 'c'};
String str = new String(data);
See the javadoc
public String(char[] value)
Allocates a new String so that it
represents the sequence of characters currently contained in the
character array argument. The contents of the character array are
copied; subsequent modification of the character array does not affect
the newly created string. Parameters: value - The initial value of the
string
http://docs.oracle.com/javase/6/docs/api/java/lang/String.html
Calling toString on an array will call the toString method from Object. Which will return you the hashCode
public String toString() Returns a string representation of the
object. In general, the toString method returns a string that
"textually represents" this object. The result should be a concise but
informative representation that is easy for a person to read. It is
recommended that all subclasses override this method. The toString
method for class Object returns a string consisting of the name of the
class of which the object is an instance, the at-sign character `#',
and the unsigned hexadecimal representation of the hash code of the
object. In other words, this method returns a string equal to the
value of:
getClass().getName() + '#' + Integer.toHexString(hashCode())
Returns: a string representation of the object.

Because arrays are objects. So calling toString() result to call the toString() method herited from the object class which is :
public String toString() {
return getClass().getName() + "#" + Integer.toHexString(hashCode());
}
In [C#112f614, [C means that it's an array of char.
If you want to print the content of your array, use Arrays.toString(char[] a)

What exactly happened in this code k.toString()? Should I never call toString method in a char array?
The toString method of a char array inherits the default toString behavior from Object, which is to simply print a unique identifier derived from the object's location in memory. So unless you want that unique identifier, there's not much point in calling k.toString(). (k being your char array)

You should likely never call toString on any sort of array. The Arrays class has many utility methods for creating string representations of arrays.

A partial answer to this question: "What exactly happened in this code k.toString()?"
toString() is inherited from java.lang.Object and not overridden. The implementation just print the canonical class name plus the #-letter plus the hashcode. That is all. Therefore calling this methode is not useful for applications and is just for debugging purposes in IDEs to at least enlighten which type of object is there.

String can take a char array as a constructor.
String s = new String(k);

Android how to get a String from the TextView to a String

I know how to take integer value to string like
String s = st.getText().toString(0;
but my question is how we will take for a character... suppose the value ofa textView txt1 = 'A' so how we will take the value to a string str1..
String str1 = txt1.getText().toString();
is it correct....?

TextView.getText() return java.lang.CharSequence , and ideally you should be able to apply toString() to get the String value. But, however,
from CharSequence java doc
This interface does not refine the general contracts of the equals and
hashCode methods. The result of comparing two objects that implement
CharSequence is therefore, in general, undefined. Each object may be
implemented by a different class, and there is no guarantee that each
class will be capable of testing its instances for equality with those
of the other. It is therefore inappropriate to use arbitrary
CharSequence instances as elements in a set or as keys in a map.
CharSequence is an interface( though toString() appears as declared), it should work provided the CharSequence implementer did their job properly. To avoid any suprises, you can try a different approch
final StringBuilder sb = new StringBuilder(charSequence.length());
sb.append(charSequence);
return sb.toString();

String str1 = txt1.getText().toString();
Yes. It's the right answer to get the string value from string .

If getText() already returns a String, your job is already done for you. It's a string to begin with.
If you absolutely must create a String from a single char value, you can do so with the constructor that takes a char[] as an argument: new String(new char[] {value}).
If, as Satheesh stated above, it returns a CharSequence, there is also a String constructor that takes that as a parameter. Thus, it may be best to declare a new String(txt1.getText()) rather than relying on the implementation of the returned CharSequence's toString() method.

String to Char Array and Char array to String Conversion

In my program I am getting a string from Database result set and convert it to char array like this:
emp.nid = rs.getString("nid").toCharArray();
In this part there is no error. The String is successfully converted to char array.
But I have another code like this:
nid_txt.setText(emp.nid.toString());
This prints some freaky text. Not the original. Why was this happens? Please help me.

You're calling toString on a char[] - and that inherits the implementation from Object, so you get the char[].class name, # and then the hash of the object. Instead, call the String(char[]) constructor:
nid_txt.setText(new String(emp.nid));

This happens because the toString() method is the String representation of the object, and not the String of what it contains.
Try doing like this:
nid_txt.setText(new String(emp.nid));

instead of foo.toString() do new String(foo).

You are calling the toString() on the array object. Try:
new String(emp.nid);
and you should see better results.

assuming that emp.nid is byte array second sentence is completely wrong. toString() method in such object won't work. Try insted creating new String based on byte array:
String s = new String(emp.nid);
nid_txt.setText(s);

Increment last letter of a string

Here's where I wish Java's String class had a replaceLast method, bu it doesn't and I'm getting the wrong results with my code.
I'm writing a program that searches a data structure for any items that match a string prefix. However, since I'm using an Iterator, the last item returned by the iter.next() call doesn't match the pattern, so I want to change the search string so that the last character of the query is increased by one letter. My testing code is returning [C#b82368 with this code and An as titleSearch:
public String changeLastCharacter(String titleSearch) {
char[] temp= titleSearch.toCharArray();
char lastLetter= temp[temp.length-1];
lastLetter++;
temp[temp.length-1]= lastLetter;
String newTitleSearch= temp.toString();
return newTitleSearch;
}
First, what is the cause of the output from this code?
Second, is there a better way to execute my solution?

You want:
newTitleSearch = new String(temp);
The toString method is not overridden for arrays; it's the usual Object.toString, intended for debugging. The above actually creates a string of the characters. An alternative is:
int len = titleSearch.length();
String allButLast = titleSearch.substring(0, len - 1);
newTitleSearch = allButLast + new Character(titleSearch.charAt(len - 1) + 1);

Whenever you see unexpected output like ....#<hex-digits>, the chances are that you are accidentally using toString() on some object whose class inherits the default implementation from Object.
The default toString() method returns a String whose value consists of the type name for the object combined with the object's "identity hash code" as hex digits. In your case the [C part is the type name for a char[] object. The '[' means "array of" and the 'C' means the char primitive type.
The rules for forming the type names used in the default toString() method are fully documented in the javadocs for java.lang.Class.getName().

Your problem is temp.toString(). Try String newTitleSearch = new String(temp); instead.
I figured this out by System.out.println(temp[0]+","+temp[1]); after temp[1] add been assigned to the incremented value. You could do this even easier by using your IDE's debugger.
Since the array was being assigned properly, the problem had to be in the toString().