com.github.robtimus.obfuscation

Class Obfuscator

java.lang.Object

com.github.robtimus.obfuscation.Obfuscator

public abstract class Obfuscator
extends Object

An object that will obfuscate CharSequences or the contents of Readers.

Author:

Rob Spoor

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	Obfuscator.ObfuscatorFunction A function that can parts of CharSequences.
static class	Obfuscator.PortionBuilder A builder for obfuscators that obfuscate a specific portion of their input.
static class	Obfuscator.Prefix A prefix of a specific length that uses a specific obfuscator.
static class	Obfuscator.SplitPoint A point in a CharSequence or Reader to split obfuscation.

Constructor Summary

Constructors

Constructor and Description
Obfuscator()

Method Summary

Modifier and Type	Method and Description
static Obfuscator	all() Returns an immutable obfuscator that replaces all characters with *.
static Obfuscator	all(char maskChar) Returns an immutable obfuscator that replaces all characters with a specific character.
static Obfuscator	fixedLength(int fixedLength) Returns an immutable obfuscator that replaces all characters with a fixed number of *.
static Obfuscator	fixedLength(int fixedLength, char maskChar) Returns an immutable obfuscator that replaces all characters with a fixed number of a specific character.
static Obfuscator	fixedValue(String fixedValue) Returns an immutable obfuscator that replaces all characters with a fixed value.
static Obfuscator	fromFunction(Function<? super CharSequence,? extends CharSequence> function) Returns an obfuscator that uses a function to obfuscate text.
static Obfuscator	fromFunction(Obfuscator.ObfuscatorFunction function) Returns an obfuscator that uses a function to obfuscate text.
static Obfuscator	none() Returns an immutable obfuscator that does not obfuscate anything.
<E> Collection<E>	obfuscateCollection(Collection<E> collection) Obfuscates a collection.
<E> Collection<E>	obfuscateCollection(Collection<E> collection, Function<? super E,? extends CharSequence> elementRepresentation) Obfuscates a collection.
<E> List<E>	obfuscateList(List<E> list) Obfuscates a list.
<E> List<E>	obfuscateList(List<E> list, Function<? super E,? extends CharSequence> elementRepresentation) Obfuscates a list.
<K,V> Map<K,V>	obfuscateMap(Map<K,V> map) Obfuscates a map.
<K,V> Map<K,V>	obfuscateMap(Map<K,V> map, Function<? super V,? extends CharSequence> valueRepresentation) Obfuscates a map.
<T> Obfuscated<T>	obfuscateObject(T value) Obfuscates a value.
<T> Obfuscated<T>	obfuscateObject(T value, Supplier<? extends CharSequence> representation) Obfuscates a value.
<E> Set<E>	obfuscateSet(Set<E> set) Obfuscates a set.
<E> Set<E>	obfuscateSet(Set<E> set, Function<? super E,? extends CharSequence> elementRepresentation) Obfuscates a set.
CharSequence	obfuscateText(CharSequence s) Obfuscates the contents of a CharSequence.
void	obfuscateText(CharSequence s, Appendable destination) Obfuscates the contents of a CharSequence.
abstract CharSequence	obfuscateText(CharSequence s, int start, int end) Obfuscates parts of the contents of a CharSequence.
abstract void	obfuscateText(CharSequence s, int start, int end, Appendable destination) Obfuscates parts of the contents of a CharSequence.
void	obfuscateText(CharSequence s, int start, int end, StringBuffer destination) Obfuscates parts of the contents of a CharSequence.
void	obfuscateText(CharSequence s, int start, int end, StringBuilder destination) Obfuscates parts of the contents of a CharSequence.
void	obfuscateText(CharSequence s, StringBuffer destination) Obfuscates the contents of a CharSequence.
void	obfuscateText(CharSequence s, StringBuilder destination) Obfuscates the contents of a CharSequence.
CharSequence	obfuscateText(Reader input) Obfuscates the contents of a Reader.
abstract void	obfuscateText(Reader input, Appendable destination) Obfuscates the contents of a Reader.
static Obfuscator.PortionBuilder	portion() Returns a builder for obfuscators that obfuscate a specific portion of their input.
abstract Writer	streamTo(Appendable destination) Returns a writer that, when written to, will obfuscate its contents.
Obfuscator.Prefix	untilLength(int prefixLength) Creates a prefix that can be used to chain another obfuscator to this obfuscator.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Obfuscator

public Obfuscator()

Method Detail

obfuscateText

public CharSequence obfuscateText(CharSequence s)

Obfuscates the contents of a CharSequence.

Parameters:

s - The CharSequence with the contents to obfuscate.

Returns:

The obfuscated contents.

Throws:

NullPointerException - If the given CharSequence is null.

obfuscateText

public abstract CharSequence obfuscateText(CharSequence s,
                                           int start,
                                           int end)

Obfuscates parts of the contents of a CharSequence.

Parameters:

s - The CharSequence with the contents to obfuscate.

start - The index in the CharSequence to start obfuscating, inclusive.

end - The index in the CharSequence to end obfuscating, exclusive.

Returns:

The obfuscated contents.

Throws:

NullPointerException - If the given CharSequence is null.

IndexOutOfBoundsException - If the given start index is negative or larger than the given end index, or if the given end index is larger than the given CharSequence's length.

obfuscateText

public void obfuscateText(CharSequence s,
                          StringBuilder destination)

Obfuscates the contents of a CharSequence.

Parameters:

s - The CharSequence with the contents to obfuscate.

destination - The StringBuilder to append the obfuscated contents to.

Throws:

NullPointerException - If the given CharSequence or StringBuilder is null.

obfuscateText

public void obfuscateText(CharSequence s,
                          int start,
                          int end,
                          StringBuilder destination)

Obfuscates parts of the contents of a CharSequence.

Parameters:

s - The CharSequence with the contents to obfuscate.

start - The index in the CharSequence to start obfuscating, inclusive.

end - The index in the CharSequence to end obfuscating, exclusive.

destination - The StringBuilder to append the obfuscated contents to.

Throws:

NullPointerException - If the given CharSequence or StringBuilder is null.

IndexOutOfBoundsException - If the given start index is negative or larger than the given end index, or if the given end index is larger than the given CharSequence's length.

obfuscateText

public void obfuscateText(CharSequence s,
                          StringBuffer destination)

Obfuscates the contents of a CharSequence.

Parameters:

s - The CharSequence with the contents to obfuscate.

destination - The StringBuffer to append the obfuscated contents to.

Throws:

NullPointerException - If the given CharSequence or StringBuffer is null.

obfuscateText

public void obfuscateText(CharSequence s,
                          int start,
                          int end,
                          StringBuffer destination)

Obfuscates parts of the contents of a CharSequence.

Parameters:

s - The CharSequence with the contents to obfuscate.

start - The index in the CharSequence to start obfuscating, inclusive.

end - The index in the CharSequence to end obfuscating, exclusive.

destination - The StringBuffer to append the obfuscated contents to.

Throws:

NullPointerException - If the given CharSequence or StringBuffer is null.

IndexOutOfBoundsException - If the given start index is negative or larger than the given end index, or if the given end index is larger than the given CharSequence's length.

obfuscateText

public void obfuscateText(CharSequence s,
                          Appendable destination)
                   throws IOException

Obfuscates the contents of a CharSequence.

Parameters:

s - The CharSequence with the contents to obfuscate.

destination - The Appendable to append the obfuscated contents to.

Throws:

NullPointerException - If the given CharSequence or Appendable is null.

IOException - If an I/O error occurs.

obfuscateText

public abstract void obfuscateText(CharSequence s,
                                   int start,
                                   int end,
                                   Appendable destination)
                            throws IOException

Obfuscates parts of the contents of a CharSequence.

Parameters:

s - The CharSequence with the contents to obfuscate.

start - The index in the CharSequence to start obfuscating, inclusive.

end - The index in the CharSequence to end obfuscating, exclusive.

destination - The Appendable to append the obfuscated contents to.

Throws:

NullPointerException - If the given CharSequence or Appendable is null.

IndexOutOfBoundsException - If the given start index is negative or larger than the given end index, or if the given end index is larger than the given CharSequence's length.

IOException - If an I/O error occurs.

obfuscateText

public CharSequence obfuscateText(Reader input)
                           throws IOException

Obfuscates the contents of a Reader.

Parameters:

input - The Reader with the contents to obfuscate.

Returns:

The obfuscated contents.

Throws:

NullPointerException - If the given Reader is null.

IOException - If an I/O error occurs.

obfuscateText

public abstract void obfuscateText(Reader input,
                                   Appendable destination)
                            throws IOException

Obfuscates the contents of a Reader.

Parameters:

input - The Reader with the contents to obfuscate.

destination - The Appendable to append the obfuscated contents to.

Throws:

NullPointerException - If the given Reader or Appendable is null.

IOException - If an I/O error occurs.

obfuscateObject

public final <T> Obfuscated<T> obfuscateObject(T value)

Obfuscates a value. The value's string representation will be used to obfuscate the value.

Type Parameters:

T - The type of value to obfuscate.

Parameters:

value - The value to obfuscate.

Returns:

An Obfuscated wrapper around the given value.

Throws:

NullPointerException - If the given value is null.

obfuscateObject

public final <T> Obfuscated<T> obfuscateObject(T value,
                                               Supplier<? extends CharSequence> representation)

Obfuscates a value.

Type Parameters:

T - The type of value to obfuscate.

Parameters:

value - The value to obfuscate.

representation - A supplier for the character representation that will be used to obfuscate the value. This can be used for values that don't have a sensible string representation of their own.

Returns:

An Obfuscated wrapper around the given value.

Throws:

NullPointerException - If the given value is or supplier is null.

obfuscateList

public final <E> List<E> obfuscateList(List<E> list)

Obfuscates a list. For each element, the element's string representation will be used to obfuscate the element.

The result will be a list that will behave exactly the same as the given list, except it will obfuscate each element when its toString() method is called. This is different from obfuscateObject(Object) because it will not obfuscate the list structure or the number of elements.

Type Parameters:

E - The list's element type.

Parameters:

list - The list to obfuscate.

Returns:

An obfuscating list wrapper around the given list.

Throws:

NullPointerException - If the given list is null.

obfuscateList

public final <E> List<E> obfuscateList(List<E> list,
                                       Function<? super E,? extends CharSequence> elementRepresentation)

Obfuscates a list. For each element, a function will be used to create the element's character representation that will be used to obfuscate the element.

The result will be a list that will behave exactly the same as the given list, except it will obfuscate each element when its toString() method is called. This is different from obfuscateObject(Object) because it will not obfuscate the list structure or the number of elements.

Type Parameters:

E - The list's element type.

Parameters:

list - The list to obfuscate.

elementRepresentation - The function to use to create the character representation for each element.

Returns:

An obfuscating list wrapper around the given list.

Throws:

NullPointerException - If the given list or function is null.

Since:

1.3

obfuscateSet

public final <E> Set<E> obfuscateSet(Set<E> set)

Obfuscates a set. For each element, the element's string representation will be used to obfuscate the element.

The result will be a set that will behave exactly the same as the given set, except it will obfuscate each element when its toString() method is called. This is different from obfuscateObject(Object) because it will not obfuscate the set structure or the number of elements.

Type Parameters:

E - The set's element type.

Parameters:

set - The set to obfuscate.

Returns:

An obfuscating set wrapper around the given set.

Throws:

NullPointerException - If the given set is null.

obfuscateSet

public final <E> Set<E> obfuscateSet(Set<E> set,
                                     Function<? super E,? extends CharSequence> elementRepresentation)

Obfuscates a set. For each element, a function will be used to create the element's character representation that will be used to obfuscate the element.

The result will be a set that will behave exactly the same as the given set, except it will obfuscate each element when its toString() method is called. This is different from obfuscateObject(Object) because it will not obfuscate the set structure or the number of elements.

Type Parameters:

E - The set's element type.

Parameters:

set - The set to obfuscate.

elementRepresentation - The function to use to create the character representation for each element.

Returns:

An obfuscating set wrapper around the given set.

Throws:

NullPointerException - If the given set or function is null.

Since:

1.3

obfuscateCollection

public final <E> Collection<E> obfuscateCollection(Collection<E> collection)

Obfuscates a collection. For each element, the element's string representation will be used to obfuscate the element.

The result will be a collection that will behave exactly the same as the given collection, except it will obfuscate each element when its toString() method is called. This is different from obfuscateObject(Object) because it will not obfuscate the collection structure or the number of elements.

Type Parameters:

E - The collection's element type.

Parameters:

collection - The collection to obfuscate.

Returns:

An obfuscating collection wrapper around the given collection.

Throws:

NullPointerException - If the given collection is null.

obfuscateCollection

public final <E> Collection<E> obfuscateCollection(Collection<E> collection,
                                                   Function<? super E,? extends CharSequence> elementRepresentation)

Obfuscates a collection. For each element, a function will be used to create the element's character representation that will be used to obfuscate the element.

The result will be a collection that will behave exactly the same as the given collection, except it will obfuscate each element when its toString() method is called. This is different from obfuscateObject(Object) because it will not obfuscate the collection structure or the number of elements.

Type Parameters:

E - The collection's element type.

Parameters:

collection - The collection to obfuscate.

elementRepresentation - The function to use to create the character representation for each element.

Returns:

An obfuscating collection wrapper around the given collection.

Throws:

NullPointerException - If the given collection or function is null.

Since:

1.3

obfuscateMap

public final <K,V> Map<K,V> obfuscateMap(Map<K,V> map)

Obfuscates a map. For each value, the value's string representation will be used to obfuscate the value.

The result will be a map that will behave exactly the same as the given map, except it will obfuscate each value when its toString() method is called. This is different from obfuscateObject(Object) because it will not obfuscate the map structure or the number of entries.

Type Parameters:

K - The map's key type.

V - The map's value type.

Parameters:

map - The map to obfuscate.

Returns:

An obfuscating map wrapper around the given list.

Throws:

NullPointerException - If the given map is null.

obfuscateMap

public final <K,V> Map<K,V> obfuscateMap(Map<K,V> map,
                                         Function<? super V,? extends CharSequence> valueRepresentation)

Obfuscates a map. For each value, a function will be used to create the element's character representation that will be used to obfuscate the element.

The result will be a map that will behave exactly the same as the given map, except it will obfuscate each value when its toString() method is called. This is different from obfuscateObject(Object) because it will not obfuscate the map structure or the number of entries.

Type Parameters:

K - The map's key type.

V - The map's value type.

Parameters:

map - The map to obfuscate.

valueRepresentation - The function to use to create the character representation for each value.

Returns:

An obfuscating map wrapper around the given list.

Throws:

NullPointerException - If the given map or function is null.

Since:

1.3

streamTo

public abstract Writer streamTo(Appendable destination)

Returns a writer that, when written to, will obfuscate its contents. The writer should be closed to ensure all obfuscation will take place. Note that closing this writer should not close the given destination if it's Closeable or AutoCloseable.

Parameters:

destination - The destination to append the obfuscated contents to.

Returns:

A writer that, when written to, will obfuscate its contents.

untilLength

public final Obfuscator.Prefix untilLength(int prefixLength)

Creates a prefix that can be used to chain another obfuscator to this obfuscator. For the part up to the given prefix length, this obfuscator will be used; for any remaining content another obfuscator will be used. This makes it possible to easily create complex obfuscators that would otherwise be impossible using any of the other obfuscators provided by this library. For instance, it would be impossible to use only portion() to create an obfuscator that does not obfuscate the first 4 characters, then obfuscates at least 8 characters, then does not obfuscate up to 4 characters at the end. With this method it's possible to do that by combining none() and portion():

 Obfuscator obfuscator = none().untilLength(4).then(portion()
         .keepAtEnd(4)
         .atLeastFromStart(8)
         .build());
 

Parameters:

prefixLength - The length of the part to use this obfuscator.

Returns:

A prefix that can be used to chain another obfuscator to this obfuscator.

Throws:

IllegalArgumentException - If the prefix length is not larger than all previous prefix lengths in a method chain. In other words, each prefix length must be larger than its direct predecessor.

Since:

1.2

all

public static final Obfuscator all()

Returns an immutable obfuscator that replaces all characters with *. The length of obfuscated contents will be as long as the length of the source.

Returns:

An obfuscator that replaces all characters with *.

all

public static final Obfuscator all(char maskChar)

Returns an immutable obfuscator that replaces all characters with a specific character. The length of obfuscated contents will be as long as the length of the source.

Parameters:

maskChar - The character to replace with.

Returns:

An obfuscator that replaces all characters with the given mask character.

none

public static final Obfuscator none()

Returns an immutable obfuscator that does not obfuscate anything. This can be used as default value to prevent having to check for null.

Returns:

An obfuscator that does not obfuscate anything.

fixedLength

public static Obfuscator fixedLength(int fixedLength)

Returns an immutable obfuscator that replaces all characters with a fixed number of *.

Parameters:

fixedLength - The fixed length.

Returns:

An obfuscator that replaces all characters with the given number of *.

Throws:

IllegalArgumentException - If the given fixed length is negative.

fixedLength

public static Obfuscator fixedLength(int fixedLength,
                                     char maskChar)

Returns an immutable obfuscator that replaces all characters with a fixed number of a specific character.

Parameters:

fixedLength - The fixed length.

maskChar - The character to replace with.

Returns:

An obfuscator that replaces all characters with the given number of the given character.

Throws:

IllegalArgumentException - If the given fixed length is negative.

fixedValue

public static Obfuscator fixedValue(String fixedValue)

Returns an immutable obfuscator that replaces all characters with a fixed value.

Parameters:

fixedValue - The fixed value.

Returns:

An obfuscator that replaces all characters with the given fixed value.

Throws:

NullPointerException - If the given fixed value is null.

portion

public static Obfuscator.PortionBuilder portion()

Returns a builder for obfuscators that obfuscate a specific portion of their input.

Returns:

A builder for obfuscators that obfuscate a specific portion of their input.

fromFunction

public static Obfuscator fromFunction(Function<? super CharSequence,? extends CharSequence> function)

Returns an obfuscator that uses a function to obfuscate text. This method allows you to create an obfuscator using a predefined function. The returned obfuscator is immutable if the given function is.

This method differs from fromFunction(ObfuscatorFunction) in the way sub sequences are treated. This method uses CharSequence.subSequence(int, int), which may unnecessarily create new sub sequences. fromFunction(ObfuscatorFunction) on the other hand lets the function handle the sub sequencing.

Note: the function should never return null. The returned obfuscator will throw a NullPointerException if the function returns null when obfuscating text.

Parameters:

function - The function to use.

Returns:

An obfuscator that uses the given function to obfuscate text.

Throws:

NullPointerException - If the given function is null.

fromFunction

public static Obfuscator fromFunction(Obfuscator.ObfuscatorFunction function)

Returns an obfuscator that uses a function to obfuscate text. This method allows you to create an obfuscator using a predefined function. The returned obfuscator is immutable if the given function is.

This method differs from fromFunction(Function) in the way sub sequences are treated. fromFunction(Function) uses CharSequence.subSequence(int, int), which may unnecessarily create new sub sequences. This method on the other hand lets the function handle the sub sequencing.

Note: the function should never return null. The returned obfuscator will throw a NullPointerException if the function returns null when obfuscating text.

Parameters:

function - The function to use.

Returns:

An obfuscator that uses the given function to obfuscate text.

Throws:

NullPointerException - If the given function is null.

Since:

1.5