Overview | Package | Class | Tree | Deprecated | Index | Help
| J avolution v5.2 (J2SE 1.5+)
PREV PACKAGE NEXT PACKAGE | FRAMES NO FRAMES

## Package javolution.text

Provides classes and interfaces to handle text.

See:
Description

Class Summary
CharArray | This class represents a character sequence backed up by a `char` array.
CharSet | This class represents a set of characters.
Text | This class represents an immutable character sequence with fast `concatenation`, `insertion` and `deletion` capabilities (O[Log(n)]) instead of O[n] for StringBuffer/StringBuilder).
TextBuilder | This class represents an `Appendable` text whose capacity expands gently without incurring expensive resize/copy operations ever.
TextFormat<T> | This class represents the base format for text parsing and formatting; it supports `CharSequence` and `Appendable` interfaces for greater flexibility.
TextFormat.Cursor | This class represents a parsing cursor over a character sequence (or subsequence).
TypeFormat | This class provides utility methods to parse `CharSequence` into primitive types and to format primitive types into any `Appendable`.

## Package javolution.text Description

Provides classes and interfaces to handle text.

## FAQ:

1. Is parsing/formatting of floating-points numbers (e.g. `double`) equivalent to standard String/Double methods?

   With Javolution 4.1, `double` formatting/parsing is lossless and functionally the same as with the standard library. Parsing a character sequence will always result in the same number whether it is performed with `TypeFormat` or using `Double.parseDouble(String))`. When formatting a `double` number, the number of digits output is adjustable. The default (if the number of digits is unspecified) is `17` or `16` when the the 16 digits representation can be parsed back to the same `double` (mimic the standard library formatting).

   Javolution parsing/formatting do not generate garbage and has no adverse effect on GC. Better, it does not force the user to create intermediate `String` objects, any `CharSequence/Appendable` can be used! Serial parsing is also supported (cursor parameter).

2. I'm accumulating a large string, and all I want to do is append to the end of the current string, which is the better class to use, Text or TextBuilder? Bearing in mind that speed is important, but I also want to conserve memory.

   It all depends of the size of the text to append (the actual size of the document being appended has almost no impact in both cases).

   If you append one character at a time or a small text then `TextBuilder.append(Object)` is faster (the cost of copying the characters to the internal buffer is then negligeable and TextBuilder never resizes its internal arrays).

   If you append larger character sequences (the threshold might be around 20 characters) then `Text.concat(Text)` is more efficient (it avoid character copies, but creates small nodes objects instead).

3. In our project's use of strings, there are a lot of instances of directory path names, such as `"/proj/lodecase/src/com/lodecase/util/foo.java"`, and `"/proj/lodecase/src/com/lodecase/util/bar.java"`. Can the 'Text' class save us memory when strings have common prefixes?

   It depends how you build your text. For example in following code:``

          Text directoryName = Text.valueOf("/proj/lodecase/src/com/lodecase/util/");
          Text fooFileName = directoryName.plus("foo.java");
          Text barFileName = directoryName.plus("bar.java");

   The prefix (directoryName)is shared between `fooFileName` and `barFileName`.

   Text is a binary tree of blocks of characters. In the example, above, `fooFileName` is a node with `directoryName` for head and "foo.java" for tail. The tree is maintained balanced automatically through tree rotations.

Overview | Package | Class | Tree | Deprecated | Index | Help
| J avolution v5.2 (J2SE 1.5+)
PREV PACKAGE NEXT PACKAGE | FRAMES NO FRAMES

Copyright © 2005 - 2007 Javolution.