Package org.flasby.crypto

Class SecureString

java.lang.Object

org.flasby.crypto.SecureString

All Implemented Interfaces:

AutoCloseable, CharSequence

public final class SecureString
extends Object
implements CharSequence, AutoCloseable

This is not a string but a CharSequence that can be cleared of its memory. Important for handling passwords. Represents text that should be kept confidential, such as by deleting it from memory when no longer needed or garbaged collected.

Modified from an original post in stackoverflow by Melloware who modified something from OWASP.

Constructor Summary

Constructors

Constructor	Description
SecureString(int start, int end, CharSequence original)
SecureString(CharSequence original)

Method Summary

Modifier and Type	Method	Description
String	asString()	Convert array back to String but not using toString().
char	charAt(int i)
void	clear()	Manually clear the underlying array holding the characters
void	close()
int	length()
CharSequence	subSequence(int start, int end)
String	toString()	Protect against using this class in log statements.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.CharSequence

chars, codePoints, isEmpty

Constructor Details

SecureString

public SecureString(CharSequence original)

SecureString

public SecureString(int start,
 int end,
 CharSequence original)

Method Details

charAt

public char charAt(int i)

Specified by:

charAt in interface CharSequence

length

public int length()

Specified by:

length in interface CharSequence

subSequence

public CharSequence subSequence(int start,
 int end)

Specified by:

subSequence in interface CharSequence

asString

public String asString()

Convert array back to String but not using toString(). See toString() docs below. Calling should be avoided as it leaves passwords in memory which can't be cleared.

clear

public void clear()

Manually clear the underlying array holding the characters

toString

public String toString()

Protect against using this class in log statements.

Specified by:

toString in interface CharSequence

Overrides:

toString in class Object

close

public void close()

Specified by:

close in interface AutoCloseable