1. Java IO Tutorial
2. Java IO Overview
3. Java IO: Files
4. Java IO: Streams
5. Java IO: Pipes
6. Java IO: Networking
7. Java IO: Byte & Char Arrays
8. Java System.in, System.out, and System.error
9. Java IO: Input Parsing
10. Java IO: Readers and Writers
11. Java IO: Concurrent IO
12. Java IO: Exception Handling
13. Java InputStream
14. Java OutputStream
15. Java FileInputStream
16. Java FileOutputStream
17. Java RandomAccessFile
18. Java File
19. Java IO: PipedInputStream
20. Java IO: PipedOutputStream
21. Java ByteArrayInputStream
22. Java ByteArrayOutputStream
23. Java IO: FilterInputStream
24. Java IO: FilterOutputStream
25. Java BufferedInputStream
26. Java BufferedOutputStream
27. Java PushbackInputStream
28. Java IO: SequenceInputStream
29. Java DataInputStream
30. Java IO: DataOutputStream
31. Java IO: PrintStream
32. Java IO: ObjectInputStream
33. Java IO: ObjectOutputStream
34. Java IO: Serializable
35. Java Reader
36. Java Writer
37. Java InputStreamReader
38. Java OutputStreamWriter
39. Java FileReader
40. Java FileWriter
41. Java IO: PipedReader
42. Java IO: PipedWriter
43. Java IO: CharArrayReader
44. Java IO: CharArrayWriter
45. Java BufferedReader
46. Java BufferedWriter
47. Java IO: FilterReader
48. Java IO: FilterWriter
49. Java PushbackReader
50. Java IO: LineNumberReader
51. Java StreamTokenizer
52. Java IO: PrintWriter
53. Java IO: StringReader
54. Java IO: StringWriter

• CharArrayReader Example
• Creating a CharArrayReader From Part of a char Array
• Closing a CharArrayReader

The Java CharArrayReader class (java.io.CharArrayReader) enables you to read the contents of a char array as a character stream.

The Java CharArrayReader is handy when you have data in a char array, but need to pass that data to some component which can only read from a Reader (or a Reader subclass). Simply wrap the char array in a CharArrayReader and pass it to that component.

CharArrayReader Example

Here is a simple Java CharArrayReader example:

char[] chars = "123".toCharArray();

CharArrayReader charArrayReader =
    new CharArrayReader(chars);

int data = charArrayReader.read();
while(data != -1) {
  //do something with data

  data = charArrayReader.read();
}

charArrayReader.close();

This example first creates a char array from a Java string. Second, the example creates a CharArrayReader instance, passing the char array as parameter to the CharArrayReader constructor. Third, the example reads the chars one by one from the CharArrayReader, and finally the CharArrayReader is closed.

Note: The proper exception handling has been skipped here for the sake of clarity. To learn more about correct exception handling, go to Java IO Exception Handling.

Creating a CharArrayReader From Part of a char Array

It is possible to create a Java CharArrayReader from just part of a char array. Here is an example showing how to create a CharArrayReader that reads only part of a char array:

char[] chars = "0123456789".toCharArray();

int offset = 2;
int length = 6;

CharArrayReader charArrayReader =
    new CharArrayReader(chars, offset, length);

This example creates a CharArrayReader which only reads from the char with index 2 and 6 char elements forward in the char array.

Closing a CharArrayReader

Closing a CharArrayReader can be done using the close() method like this:

charArrayReader.close();

Or you can close the CharArrayReader using the Java 7 try-with-resources construct. Here is how that looks:

try(CharArrayReader charArrayReader =
    new CharArrayReader(chars, offset, length)){

    int data = charArrayReader.read();
    while(data != -1) {
        //do something with data
        data = charArrayReader.read();
    }
}

Notice that there is no explicit close() call on the CharArrayReader. The try block takes care of that.

However, since the CharArrayReader is not using any underlying system resources like files or network sockets, closing the CharArrayReader is not crucial.