X-Git-Url: http://git.indexdata.com/?a=blobdiff_plain;f=src%2Forg%2Fz3950%2Fzing%2Fcql%2FCQLNode.java;h=3e42e1e101bf35163cf343b4eb721b2cc2999399;hb=af9fc1ccd0a8d9048d0b469a72b11bead020b719;hp=326743255bd9e61ce54e86526015d7067eddf6b9;hpb=70be8275aabe87c909bf11148bb279c3e1380bb2;p=cql-java-moved-to-github.git diff --git a/src/org/z3950/zing/cql/CQLNode.java b/src/org/z3950/zing/cql/CQLNode.java index 3267432..3e42e1e 100644 --- a/src/org/z3950/zing/cql/CQLNode.java +++ b/src/org/z3950/zing/cql/CQLNode.java @@ -1,62 +1,354 @@ -// $Id: CQLNode.java,v 1.7 2002-10-30 09:19:26 mike Exp $ +// $Id: CQLNode.java,v 1.26 2007-07-03 13:36:03 mike Exp $ package org.z3950.zing.cql; +import java.util.Properties; +import java.util.Vector; /** * Represents a node in a CQL parse-tree. - * ### * - * @version $Id: CQLNode.java,v 1.7 2002-10-30 09:19:26 mike Exp $ + * @version $Id: CQLNode.java,v 1.26 2007-07-03 13:36:03 mike Exp $ */ public abstract class CQLNode { - abstract String toXCQL(int level); - abstract String toCQL(); + CQLNode() {} // prevent javadoc from documenting this - protected String indent(int level) { - String x = ""; - while (level-- > 0) { - x += " "; + /** + * Returns the name of the result-set to which this query is a + * reference, if and only if the entire query consists only of a + * result-set reference. If it's anything else, including a + * boolean combination of a result-set reference with something + * else, then null is returned instead. + * @return the name of the referenced result-set + */ + public String getResultSetName() { + return null; + } + + /** + * Translates a parse-tree into an XCQL document. + *

+ * @param level + * The number of levels to indent the top element of the XCQL + * document. This will typically be 0 when invoked by an + * application; it takes higher values when this method is + * invoked recursively for nodes further down the tree. + * @return + * A String containing an XCQL document equivalent to the + * parse-tree whose root is this node. + */ + public String toXCQL(int level) { + return toXCQL(level, null); + } + + public String toXCQL(int level, Vector prefixes) { + return toXCQL(level, prefixes, null); + } + + abstract public String toXCQL(int level, Vector prefixes, + Vector sortkeys); + + protected static String renderPrefixes(int level, Vector prefixes) { + if (prefixes == null || prefixes.size() == 0) + return ""; + String res = indent(level) + "\n"; + for (int i = 0; i < prefixes.size(); i++) { + CQLPrefix p = (CQLPrefix) prefixes.get(i); + res += indent(level+1) + "\n"; + if (p.name != null) + res += indent(level+2) + "" + p.name + "\n"; + res += indent(level+2) + + "" + p.identifier + "\n"; + res += indent(level+1) + "\n"; } - return x; - } - - // XML Quote -- - // s/&/&/g; - // s//>/g; - // This is hideously inefficient, but I just don't see a better - // way using the standard JAVA library. - // - protected String xq(String str) { - str = replace(str, "&", "&"); - str = replace(str, "<", "<"); - str = replace(str, ">", ">"); - return str; - } - - // I can't _believe_ I have to write this by hand in 2002 ... - protected static String replace(String str, String from, String to) { - StringBuffer sb = new StringBuffer(); - int ix; // index of next `from' - int offset = 0; // index of previous `from' + length(from) - - while ((ix = str.indexOf(from, offset)) != -1) { - sb.append(str.substring(offset, ix)); - sb.append(to); - offset = ix + from.length(); + return res + indent(level) + "\n"; + } + + protected static String renderSortKeys(int level, + Vector sortkeys) { + if (sortkeys == null || sortkeys.size() == 0) + return ""; + String res = indent(level) + "\n"; + for (int i = 0; i < sortkeys.size(); i++) { + ModifierSet key = sortkeys.get(i); + res += key.sortKeyToXCQL(level+1); } + return res + indent(level) + "\n"; + } + + /** + * Decompiles a parse-tree into a CQL query. + *

+ * @return + * A String containing a CQL query equivalent to the parse-tree + * whose root is this node, so that compiling that query will + * yield an identical tree. + */ + abstract public String toCQL(); + + /** + * Renders a parse-tree into a Yaz-style PQF string. + * PQF, or Prefix Query Format, is a cryptic but powerful notation + * that can be trivially mapped, one-to-one, int Z39.50 Type-1 and + * Type-101 queries. A specification for the format can be found + * in + * Chapter 7 (Supporting Tools) of the + * YAZ manual. + *

+ * @param config + * A Properties object containing configuration + * information that specifies the mapping from CQL indexes, + * relations, etc. to Type-1 attributes. The mapping + * specification is described in the CQL-Java distribution's + * sample PQF-mapping configuration file, + * etc/pqf.properties, which see. + * @return + * A String containing a PQF query equivalent to the parse-tree + * whose root is this node. + */ + abstract public String toPQF(Properties config) + throws PQFTranslationException; + + /** + * Returns a String of spaces for indenting to the specified level. + */ + protected static String indent(int level) { return Utils.indent(level); } + + /** + * Returns the argument String quoted for XML. + * For example, each occurrence of < is translated to + * &lt;. + */ + protected static String xq(String str) { return Utils.xq(str); } + + /** + * Renders a parser-tree into a BER-endoded packet representing an + * equivalent Z39.50 Type-1 query. If you don't know what that + * means, then you don't need this method :-) This is useful + * primarily for SRW-to-Z39.50 gateways. + * + * @param config + * A Properties object containing configuration + * information that specifies the mapping from CQL indexes, + * relations, etc. to Type-1 attributes. The mapping + * specification is described in the CQL-Java distribution's + * sample PQF-mapping configuration file, + * etc/pqf.properties, which see. + * @return + * A byte array containing the BER packet. + * @see + * ftp://ftp.rsasecurity.com/pub/pkcs/ascii/layman.asc + */ + abstract public byte[] toType1BER(Properties config) + throws PQFTranslationException; + + // ANS.1 classes + protected static final int UNIVERSAL = 0; + protected static final int APPLICATION = 1; + protected static final int CONTEXT = 2; + protected static final int PRIVATE = 3; + + // ASN.1 tag forms + protected static final int PRIMITIVE = 0; + protected static final int CONSTRUCTED = 1; + + // ASN.1 UNIVERSAL data types + public static final byte BOOLEAN = 1; + public static final byte INTEGER = 2; + public static final byte BITSTRING = 3; + public static final byte OCTETSTRING = 4; + public static final byte NULL = 5; + public static final byte OBJECTIDENTIFIER = 6; + public static final byte OBJECTDESCRIPTOR = 7; + public static final byte EXTERNAL = 8; + public static final byte ENUMERATED = 10; + public static final byte SEQUENCE = 16; + public static final byte SET = 17; + public static final byte VISIBLESTRING = 26; + public static final byte GENERALSTRING = 27; + + protected static final int putTag(int asn1class, int fldid, int form, + byte[] record, int offset) { + if (fldid < 31) + record[offset++] = (byte)(fldid + asn1class*64 + form*32); + else { + record[offset++] = (byte)(31 + asn1class*64 + form*32); + if (fldid < 128) + record[offset++] = (byte)(fldid); + else { + record[offset++] = (byte)(128 + fldid/128); + record[offset++] = (byte)(fldid % 128); + } + } + return offset; + } + + /** + * Put a length directly into a BER record. + * + * @param len length to put into record + * @return the new, incremented value of the offset parameter. + */ + public // ### shouldn't this be protected? + static final int putLen(int len, byte[] record, int offset) { + + if (len < 128) + record[offset++] = (byte)len; + else { + int t; + record[offset] = (byte)(lenLen(len) - 1); + for (t = record[offset]; t > 0; t--) { + record[offset+t] = (byte)(len & 0xff); + len >>= 8; + } + t = offset; + offset += (record[offset]&0xff) + 1; + record[t] += 128; // turn on bit 8 in length byte. + } + return offset; + } + + /** + * Get the length needed to represent the given length. + * + * @param length determine length needed to encode this + * @return length needed to encode given length + */ + protected // ### shouldn't this be private? + static final int lenLen(int length) { + + return ((length < 128) ? 1 : + (length < 256) ? 2 : + (length < 65536L) ? 3 : 4); + } + + /** + * Get the length needed to represent the given number. + * + * @param num determine length needed to encode this + * @return length needed to encode given number + */ + protected static final int numLen(long num) { + num = num < 0 ? -num : num; + // ### Wouldn't this be better done algorithmically? + // Or at least with the constants expressed in hex? + return ((num < 128) ? 1 : + (num < 32768) ? 2 : + (num < 8388608) ? 3 : + (num < 2147483648L) ? 4 : + (num < 549755813888L) ? 5 : + (num < 140737488355328L) ? 6 : + (num < 36028797018963968L) ? 7 : 8); + } + + /** + * Put a number into a given buffer + * + * @param num number to put into buffer + * @param record buffer to use + * @param offset offset into buffer + * @return the new, incremented value of the offset parameter. + */ + protected static final int putNum(long num, byte record[], int offset) { + int cnt=numLen(num); + + for (int count = cnt - 1; count >= 0; count--) { + record[offset+count] = (byte)(num & 0xff); + num >>= 8; + } + return offset+cnt; + } + + // Used only by the makeOID() method + private static final java.util.Hashtable madeOIDs = + new java.util.Hashtable(10); + + protected static final byte[] makeOID(String oid) { + byte[] o; + int dot, offset = 0, oidOffset = 0, value; + + if ((o = (byte[])madeOIDs.get(oid)) == null) { + o = new byte[100]; + + // Isn't this kind of thing excruciating in Java? + while (oidOffset < oid.length() && + Character.isDigit(oid.charAt(oidOffset)) == true) { + if (offset > 90) // too large + return null; + + dot = oid.indexOf('.', oidOffset); + if (dot == -1) + dot = oid.length(); + + value = Integer.parseInt(oid.substring(oidOffset, dot)); + + if (offset == 0) { // 1st two are special + if (dot == -1) // ### can't happen: -1 is reassigned above + return null; // can't be this short + oidOffset = dot+1; // skip past '.' + + dot = oid.indexOf('.', oidOffset); + if (dot == -1) + dot = oid.length(); + + // ### Eh?! + value = value * 40 + + Integer.parseInt(oid.substring(oidOffset,dot)); + } + + if (value < 0x80) { + o[offset++] = (byte)value; + } else { + int count = 0; + byte bits[] = new byte[12]; // save a 84 (12*7) bit number + + while (value != 0) { + bits[count++] = (byte)(value & 0x7f); + value >>= 7; + } + + // Now place in the correct order + while (--count > 0) + o[offset++] = (byte)(bits[count] | 0x80); + + o[offset++] = bits[count]; + } + + dot = oid.indexOf('.', oidOffset); + if (dot == -1) + break; + + oidOffset = dot+1; + } - // End of string: append last bit and we're done - sb.append(str.substring(offset)); - return sb.toString(); + byte[] ptr = new byte[offset]; + System.arraycopy(o, 0, ptr, 0, offset); + madeOIDs.put(oid, ptr); + return ptr; + } + return o; } - // Test harness - public static void main (String[] args) { - 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(0)); + public static final byte[] makeQuery(CQLNode root, Properties properties) + throws PQFTranslationException { + byte[] rpnStructure = root.toType1BER(properties); + byte[] qry = new byte[rpnStructure.length+100]; + int offset = 0; + offset = putTag(CONTEXT, 1, CONSTRUCTED, qry, offset); + qry[offset++] = (byte)(0x80&0xff); // indefinite length + offset = putTag(UNIVERSAL, OBJECTIDENTIFIER, PRIMITIVE, qry, offset); + byte[] oid = makeOID("1.2.840.10003.3.1"); // bib-1 + offset = putLen(oid.length, qry, offset); + System.arraycopy(oid, 0, qry, offset, oid.length); + offset += oid.length; + System.arraycopy(rpnStructure, 0, qry, offset, rpnStructure.length); + offset += rpnStructure.length; + qry[offset++] = 0x00; // end of query + qry[offset++] = 0x00; + byte[] q = new byte[offset]; + System.arraycopy(qry, 0, q, 0, offset); + return q; } }