org.vishia.util

Class StringSeq

java.lang.Object

org.vishia.util.StringSeq

All Implemented Interfaces:

java.lang.CharSequence

public class StringSeq
extends java.lang.Object
implements java.lang.CharSequence

This class wraps any CharSequence and provides comparable features like String for commonly usage. The difference to java.lang.String is:

• A String is guaranteed immutable, the char sequence which is referred from this class is immutable only if the programming does guarantee it.
• The advantage in comparison to java.lang.String is: If a char sequence is prepared in a StringBuilder or such adequate, it does not need an own buffer to hold the string though the StringBuilder's buffer won't be changed by any other program part. It increases the speed for string operations especially if there is a large String.

This class can be used as wrapper for both, mutable or immutable char sequences. The attribute isUnmated designates whether the char sequence is referred only by this class. This flag should be set and guaranteed by the user's programming only.

A CharSequence can be cast to a StringBuilder if its implementation class is a StringBuilder or a new StringBuilder can be build with it. The content of the StringBuilder can be changed. If it is unmated, no other usages can be affect, only the same one which changes it. In this case the CharSequence can be changed for further usage.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.CharSequence	cs
protected boolean	isUnmated If this flag is set to true, the application declares the referred cs as only referred from this.
static int	version Version, history and license.

Constructor Summary

Constructors

Constructor and Description
StringSeq()

Method Summary

Modifier and Type	Method and Description
void	change(java.lang.CharSequence src)
java.lang.StringBuilder	changeIt() Returns a StringBuilder instance which allows the content to change.
char	charAt(int index)
int	compareTo(int from1, java.lang.CharSequence s2, int from2, int nrofChars)
static StringSeq	create(java.lang.CharSequence src) An instance of this class can only build by this create method.
static StringSeq	create(java.lang.CharSequence src, boolean isUnmated) An instance of this class can only build by this create method.
int	indexOf(char cc, int fromIndex)
int	indexOf(java.lang.CharSequence str, int fromIndex)
boolean	isUnmated()
int	length()
boolean	startsWith(java.lang.CharSequence cmp)
java.lang.CharSequence	subSequence(int start, int end) A SubSequence is built as independent String in any case.
java.lang.String	substring(int start) Compatible to String.substring(int, int)
java.lang.String	substring(int start, int end) Same as subSequence(int, int) but it is compatible to String.substring(int, int)
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.CharSequence

chars, codePoints

Field Detail

version

public static final int version

Version, history and license.

• 2012-02-19 Hartmut created.

Copyright/Copyleft: For this source the LGPL Lesser General Public License, published by the Free Software Foundation is valid. It means:

1. You can use this source without any restriction for any desired purpose.
2. You can redistribute copies of this source to everybody.
3. Every user of this source, also the user of redistribute copies with or without payment, must accept this license for further using.
4. But the LPGL ist not appropriate for a whole software product, if this source is only a part of them. It means, the user must publish this part of source, but don't need to publish the whole source of the own product.
5. You can study and modify (improve) this source for own using or for redistribution, but you have to license the modified sources likewise under this LGPL Lesser General Public License. You mustn't delete this Copyright/Copyleft inscription in this source file.

If you are intent to use this sources without publishing its usage, you can get a second license subscribing a special contract with the author.

See Also:

Constant Field Values

cs

protected java.lang.CharSequence cs

isUnmated

protected boolean isUnmated

If this flag is set to true, the application declares the referred cs as only referred from this. The CharSequence can be changed only with this instance.

Constructor Detail

StringSeq

public StringSeq()

Method Detail

create

public static StringSeq create(java.lang.CharSequence src,
                               boolean isUnmated)

An instance of this class can only build by this create method. The property whether it is unmated or not should be given by the application.

Parameters:

src - any CharSequence, usual a StringBuilder.

isUnmated - it should be set to true if the src is not referred anywhere else.

Returns:

a new instance of StringSeq

create

public static StringSeq create(java.lang.CharSequence src)

An instance of this class can only build by this create method. The property whether it is unmated or not should be given by the application.

Parameters:

src - any CharSequence, usual a StringBuilder. It should be referenced never other.

isUnmated - it should be set to true if the src is not referred anywhere else.

Returns:

a new instance of StringSeq

isUnmated

public boolean isUnmated()

change

public void change(java.lang.CharSequence src)

length

public int length()

Specified by:

length in interface java.lang.CharSequence

subSequence

public java.lang.CharSequence subSequence(int start,
                                          int end)

A SubSequence is built as independent String in any case. Via this subSequennce it is not possible to change the referred char sequence.

Specified by:

subSequence in interface java.lang.CharSequence

See Also:

CharSequence.subSequence(int, int)

substring

public java.lang.String substring(int start,
                                  int end)

Same as subSequence(int, int) but it is compatible to String.substring(int, int)

Parameters:

start -

end -

Returns:

substring

public java.lang.String substring(int start)

Compatible to String.substring(int, int)

Parameters:

start -

Returns:

charAt

public char charAt(int index)

Specified by:

charAt in interface java.lang.CharSequence

compareTo

public int compareTo(int from1,
                     java.lang.CharSequence s2,
                     int from2,
                     int nrofChars)

startsWith

public boolean startsWith(java.lang.CharSequence cmp)

indexOf

public int indexOf(char cc,
                   int fromIndex)

indexOf

public int indexOf(java.lang.CharSequence str,
                   int fromIndex)

changeIt

public java.lang.StringBuilder changeIt()

Returns a StringBuilder instance which allows the content to change.

Returns:

either the same instance which is referenced with cs or a new instance of a StringBuilder if cs didn't reference a StringBuilder. In this case cs references this new StrringBuilder too.

toString

public java.lang.String toString()

Specified by:

toString in interface java.lang.CharSequence

Overrides:

toString in class java.lang.Object