https://github.com/meyfa/nsdlib
Nassi–Shneiderman diagrams (structograms) with Java
https://github.com/meyfa/nsdlib
drawing library nassi-shneiderman-diagrams nsd reader rendering structograms structorizer
Last synced: over 1 year ago
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Nassi–Shneiderman diagrams (structograms) with Java
- Host: GitHub
- URL: https://github.com/meyfa/nsdlib
- Owner: meyfa
- License: mit
- Created: 2017-02-20T05:49:05.000Z (over 9 years ago)
- Default Branch: master
- Last Pushed: 2020-08-04T16:50:26.000Z (almost 6 years ago)
- Last Synced: 2025-01-28T23:31:24.107Z (over 1 year ago)
- Topics: drawing, library, nassi-shneiderman-diagrams, nsd, reader, rendering, structograms, structorizer
- Language: Java
- Size: 101 KB
- Stars: 1
- Watchers: 3
- Forks: 1
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# nsdlib
[](https://travis-ci.com/meyfa/nsdlib)
[](https://codeclimate.com/github/meyfa/nsdlib/test_coverage)
[](https://codeclimate.com/github/meyfa/nsdlib/maintainability)
This is a Java library for working with [Nassi-Shneiderman diagrams](https://en.wikipedia.org/wiki/Nassi–Shneiderman_diagram)
(structograms).
It offers the following functionality:
* **Construct elements through code**
- All standard block types supported
* **Read structograms from files**
- Currently only support for the [Structorizer](http://structorizer.fisch.lu/)
format, but easy to add your own
* **Render structograms as images**
- Basic layouting, dynamic size calculation
- High amount of abstraction through `RenderAdapter` (AWT adapter included;
support for custom adapters for other targets, e.g. Android)
## Reading a Structogram
The following code reads a structogram stored in Structorizer's XML format.
```java
NSDReader reader = new StructorizerReader();
NSDRoot root;
File file = new File("/path/to/file.nsd");
try (FileInputStream in = new FileInputStream(file)) {
root = reader.read(in);
} catch (NSDReaderException | IOException e) {
e.printStackTrace();
}
// do something with `root`
```
Feel free to submit a PR or open an issue if you require support for other
formats. The custom reader should implement the `NSDReader` interface.
## Rendering a Structogram
To render a structogram (or part of one), the following steps need to be done:
1. Convert the element into a `RenderPart` (do this for the root element).
2. Layout the render part.
3. Render the actual image.
The following example uses the `AwtRenderer` for rendering to a `BufferedImage`,
but you can easily substitute a custom renderer instead.
```java
AwtRenderer renderer = new AwtRenderer();
// 1. convert (`diagram` is an instance of `NSDRoot`)
RenderPart part = diagram.toRenderPart();
// 2. layout
part.layout(renderer.createContext());
// optional: get the resulting size
// Size s = part.getSize();
// 3. render
BufferedImage img = renderer.render(part);
```
## Manual Structogram Construction
Constructing a structogram with code is as simple as invoking a few
constructors.
```java
NSDRoot diagram = new NSDRoot("When start clicked");
NSDDecision dec = new NSDDecision("(pick random 1 to 10) = 1");
{
dec.getThen().addChild(new NSDInstruction("say \"You're lucky!\""));
dec.getElse().addChild(new NSDInstruction("say \"Not so lucky.\""));
}
diagram.addChild(dec);
NSDForever forever = new NSDForever(Arrays.asList(
new NSDInstruction("wait 1 secs")
));
diagram.addChild(forever);
// etc
```
## Element Types
The base class for every element is `nsdlib.elements.NSDElement`. Elements that
contain other elements extend its subclass `nsdlib.elements.NSDContainer`.
| Type | Package | Class |
| -------------------- | ------------------------------ | ------------------ |
| Root element | `nsdlib.elements` | `NSDRoot` |
| Instruction | `nsdlib.elements` | `NSDInstruction` |
| If/Then/Else | `nsdlib.elements.alternatives` | `NSDDecision` |
| Switch-Case | `nsdlib.elements.alternatives` | `NSDCase` |
| Test-first loop | `nsdlib.elements.loops` | `NSDTestFirstLoop` |
| Test-last loop | `nsdlib.elements.loops` | `NSDTestLastLoop` |
| Unconditional loop | `nsdlib.elements.loops` | `NSDForever` |
| Concurrent execution | `nsdlib.elements.parallel` | `NSDParallel` |