-$Header: /home/cvsroot/cql-java/README,v 1.1 2002-10-24 15:57:56 mike Exp $
+$Id: README,v 1.8 2002-11-01 23:45:28 mike Exp $
cql-java -- a free CQL compiler for Java
This project provides a set of classes for representing a CQL parse
-tree (CQLBooleanNode, CQLTermNode, etc.) and a Compiler class which
+tree (CQLBooleanNode, CQLTermNode, etc.) and a CQLCompiler class which
builds a parse tree given a CQL query as input. It also provides
-compiler back-ends to render out the parse tree either as XCQL or
-Yaz-style Prefix Query Format (PQF).
+compiler back-ends to render out the parse tree as XCQL (the XML
+representation), as PQF (Yaz-style Prefix Query Format) and as CQL
+(i.e. decompiling the parse-tree). Oh, and there's a random query
+generator, too.
CQL is "Common Query Language", a new query language designed under
the umbrella of the ZING initiative (Z39.59-International Next
import org.z3950.zing.cql.*
+ // Building a parse-tree by hand
+ CQLNode n1 = new CQLTermNode("dc.author", "=", "kernighan");
+ CQLNode n2 = new CQLTermNode("dc.title", "all", "elements style");
+ CQLNode root = new CQLAndNode(n1, n2);
+ System.out.println(root.toXCQL(3));
+
+ // Parsing a CQL query
CQLParser parser = new CQLParser();
CQLNode root = parser.parse("title=dinosaur");
- print root.toXCQL();
- print root.toPQF(qualSet);
+ System.out.println(root.toXCQL(0));
+ System.out.println(root.toCQL());
+ System.out.println(root.toPQF(qualSet));
// ... where `qualSet' specifies CQL-qualfier => Z-attr mapping
DESCRIPTION
-----------
-Se the automatically generated class documentation in the "doc"
-subdirectory. (### It's not there yet, of course)
+See the automatically generated class documentation in the "doc"
+subdirectory. (It's not all there yet, but it's coming.)
AUTHOR
restrictive) until I say otherwise.
+TESTING
+-------
+
+Ways of testing the parser and other components include:
+
+* Generate a random tree with CQLGenerate, take a copy, and
+ canonicalise it with CQLparser -c. Since the CQLGenerate output is
+ in canonical form anyway, the before-and-after versions should be
+ identical.
+
+* ... others :-)
+
+
SEE ALSO
--------
Adam Dickmeiss's CQL compiler, written in C.
Rob Sanderson's CQL compiler, written in Python.
-All the other free CQL compilers everyone's going to write.
+All the other free CQL compilers everyone's going to write :-)
+
+
+TO DO
+-----
+
+* Allow CQLGenerate test-harness to take some of its configuration
+ parameters on the command-line as well as or instead of a file.
+
+* Some niceties for the cql-decompiling back-end:
+ * don't emit redundant parentheses.
+ * don't put spaces around relations that don't need them.
+
+* Write pqn-generating back-end (will need to be driven from a
+ configuation file specifying how to represent the qualifiers,
+ relations, relation modifiers and wildcard characters as z39.50
+ attributes.)
+
+* Consider the utility of yet another back-end that translates a
+ CQLNode tree into a Type-1 query tree using the JZKit data
+ structures. That would be nice so that CQL could become a JZKit
+ query-type; but you could achieve the same effect by generating PQN,
+ and running that through JZKit's existing PQN-to-Type-1 compiler.
+
+* Refinements to random query generator:
+ * Generate relation modifiers
+ * Proximity support
+ * Don't always generate qualifier/relation for terms
+ * Better selection of qualifier (configurable?)
+ * Better selection of terms (from a dictionary file?)
+ * Introduce wildcard characters into generated terms
+ * Generate multi-word terms
+
+* Write fuller "javadoc" comments.
+
+* Write generic test suite.
+
projects / cql-java-moved-to-github.git / blobdiff