JAL-2344 groovy script that registers a new file format

diff --git a/examples/groovy/fileFormat.groovy b/examples/groovy/fileFormat.groovy
new file mode 100644 (file)
index 0000000..137fec6
--- /dev/null
+++ b/examples/groovy/fileFormat.groovy
@@ -0,0 +1,109 @@
+import jalview.datamodel.AlignmentI
+import jalview.datamodel.SequenceI
+import jalview.datamodel.Sequence
+import jalview.io.FileFormatI
+import jalview.io.FileFormats
+import jalview.io.AlignmentFileI
+import jalview.io.FileParse
+import jalview.io.AlignFile
+
+/*
+ * Example script that registers a new alignment file format 
+ * consisting of lines like
+ * !I=<sequence id>
+ * !S=<sequence string>
+ */
+
+/*
+ * A parser class to read or write the format
+ */
+class MyParser extends AlignFile 
+{
+  /*
+   * Constructor for reading a file; the superclass
+   * constructor will call the parse() method
+   */
+  MyParser(FileParse src) 
+  {
+    super(src)
+  }
+
+  /*
+   * Constructor for writing out an alignment
+   */
+  MyParser(AlignmentI al) 
+  {
+  }
+  
+  /*
+   * Parse a formatted data file (with no error checking!)
+   */
+  void parse() 
+  {
+    String id
+    String line
+    while ((line = nextLine()) != null) 
+    {
+      if (line.startsWith('!I='))
+      {
+        int pos = line.indexOf('/')
+        id = line.substring(3, pos == -1 ? line.length() : pos)
+      } else if (line.startsWith('!S='))
+      {
+        String seq = line.substring(3)
+        addSequence(new Sequence(id, seq))
+      }
+    }
+  }
+  
+  /*
+   * Print the formatted sequences
+   * (addSuffix always defaults to true as no user preference for it)
+   */
+  String print(SequenceI[] seqs, boolean addSuffix) 
+  {
+      StringBuilder sb = new StringBuilder()
+      for (SequenceI seq : seqs) 
+      {
+          sb.append('!I=').append(seq.getDisplayId(addSuffix)).append('\n')
+          sb.append('!S=').append(seq.getSequenceAsString()).append('\n')
+      }
+      sb.toString()
+  }
+}
+
+/*
+ * A closure that defines the 'Groovy example' file format,
+ * delegating to MyParser for reading and writing
+ */
+def myFormat = { ->
+  [
+    getName: { -> 'Groovy example' },
+    
+    toString: { -> getName() },
+    
+    getExtensions: { -> 'grv' },
+    
+    getReader: { FileParse source -> new MyParser(source) },
+    
+    getWriter: { AlignmentI al -> new MyParser(al) },
+    
+    isReadable: { -> true },
+    
+    isWritable: { -> true },
+    
+    isTextFormat: { -> true },
+    
+    isStructureFile: { -> false },
+    
+    isComplexAlignFile: { -> false },
+
+   ] as FileFormatI
+}
+
+/*
+ * Register the file format. After running this script in Jalview's
+ * Groovy console, the new format should be shown in open file,
+ * save file, and output to textbox menu options.
+ */
+FileFormats.instance.registerFileFormat(myFormat())