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1 package net.sf.saxon.style;
2 import net.sf.saxon.expr.*;
3 import net.sf.saxon.instruct.Executable;
4 import net.sf.saxon.instruct.ForEachGroup;
5 import net.sf.saxon.om.AttributeCollection;
6 import net.sf.saxon.om.Axis;
7 import net.sf.saxon.pattern.Pattern;
8 import net.sf.saxon.pattern.PatternSponsor;
9 import net.sf.saxon.trans.XPathException;
10 import net.sf.saxon.value.EmptySequence;
11 import net.sf.saxon.value.SequenceType;
12
13 import java.util.Comparator  ;
14
15
19
20 public final class XSLForEachGroup extends StyleElement {
21
22 private Expression select = null;
23 private Expression groupBy = null;
24 private Expression groupAdjacent = null;
25 private Pattern starting = null;
26 private Pattern ending = null;
27 private String collationName;
28
29
33
34 public boolean isInstruction() {
35 return true;
36 }
37
38
41
42 protected boolean isPermittedChild(StyleElement child) {
43 return (child instanceof XSLSort);
44 }
45
46
50
51 public boolean mayContainSequenceConstructor() {
52 return true;
53 }
54
55 public void prepareAttributes() throws XPathException {
56
57 AttributeCollection atts = getAttributeList();
58
59 String selectAtt = null;
60 String groupByAtt = null;
61 String groupAdjacentAtt = null;
62 String startingAtt = null;
63 String endingAtt = null;
64
65 for (int a=0; a<atts.getLength(); a++) {
66 int nc = atts.getNameCode(a);
67 String f = getNamePool().getClarkName(nc);
68 if (f==StandardNames.SELECT) {
69 selectAtt = atts.getValue(a);
70 } else if (f==StandardNames.GROUP_BY) {
71 groupByAtt = atts.getValue(a);
72 } else if (f==StandardNames.GROUP_ADJACENT) {
73 groupAdjacentAtt = atts.getValue(a);
74 } else if (f==StandardNames.GROUP_STARTING_WITH) {
75 startingAtt = atts.getValue(a);
76 } else if (f==StandardNames.GROUP_ENDING_WITH) {
77 endingAtt = atts.getValue(a);
78 } else if (f==StandardNames.COLLATION) {
79 collationName = atts.getValue(a).trim();
80 } else {
81 checkUnknownAttribute(nc);
82 }
83 }
84
85 if (selectAtt==null) {
86 reportAbsence("select");
87 select = EmptySequence.getInstance(); } else {
89 select = makeExpression(selectAtt);
90 }
91
92 int c = (groupByAtt==null ? 0 : 1) +
93 (groupAdjacentAtt==null ? 0 : 1) +
94 (startingAtt==null ? 0 : 1) +
95 (endingAtt==null ? 0 : 1);;
96 if (c!=1) {
97 compileError("Exactly one of the attributes group-by, group-adjacent, group-starting-with, " +
98 "and group-ending-with must be specified", "XTSE1080");
99 }
100
101 if (groupByAtt != null) {
102 groupBy = makeExpression(groupByAtt);
103 }
104
105 if (groupAdjacentAtt != null) {
106 groupAdjacent = makeExpression(groupAdjacentAtt);
107 }
108
109 if (startingAtt != null) {
110 starting = makePattern(startingAtt);
111 }
112
113 if (endingAtt != null) {
114 ending = makePattern(endingAtt);
115 }
116
117 if (collationName!=null && groupBy==null && groupAdjacent==null) {
118 compileError("A collation may be specified only if group-by or group-adjacent is specified", "XTSE1090");
119 }
120 }
121
122 public void validate() throws XPathException {
123 checkWithinTemplate();
124 checkSortComesFirst(false);
125 select = typeCheck("select", select);
126
127 ExpressionLocation locator = new ExpressionLocation(this);
128 if (groupBy != null) {
129 groupBy = typeCheck("group-by", groupBy);
130 try {
131 RoleLocator role =
132 new RoleLocator(RoleLocator.INSTRUCTION, "xsl:for-each-group/group-by", 0, null);
133 role.setSourceLocator(locator);
134 groupBy = TypeChecker.staticTypeCheck(groupBy,
135 SequenceType.ATOMIC_SEQUENCE,
136 false, role, getStaticContext());
137 } catch (XPathException err) {
138 compileError(err);
139 }
140 } else if (groupAdjacent != null) {
141 groupAdjacent = typeCheck("group-adjacent", groupAdjacent);
142 try {
143 RoleLocator role =
144 new RoleLocator(RoleLocator.INSTRUCTION, "xsl:for-each-group/group-adjacent", 0, null);
145 role.setSourceLocator(locator);
146 role.setErrorCode("XTTE1100");
147 groupAdjacent = TypeChecker.staticTypeCheck(groupAdjacent,
148 SequenceType.SINGLE_ATOMIC,
149 false, role, getStaticContext());
150 } catch (XPathException err) {
151 compileError(err);
152 }
153 }
154
155 starting = typeCheck("starting", starting);
156 ending = typeCheck("ending", ending);
157
158 if (starting != null || ending != null) {
159 try {
160 RoleLocator role =
161 new RoleLocator(RoleLocator.INSTRUCTION, "xsl:for-each-group/select", 0, null);
162 role.setSourceLocator(locator);
163 role.setErrorCode("XTTE1120");
164 select = TypeChecker.staticTypeCheck(select,
165 SequenceType.NODE_SEQUENCE,
166 false, role, getStaticContext());
167 } catch (XPathException err) {
168 String prefix = (starting != null ?
169 "With group-starting-with attribute: " :
170 "With group-ending-with attribute: ");
171 compileError(prefix + err.getMessage(), err.getErrorCodeLocalPart());
172 }
173 }
174 }
175
176 public Expression compile(Executable exec) throws XPathException {
177
178 Comparator collator = null;
179 if (collationName != null) {
180 collator = getPrincipalStylesheet().findCollation(collationName);
181 if (collator==null) {
182 compileError("The collation name '" + collationName + "' has not been defined", "XTDE1110");
183 }
184 }
185
186 byte algorithm = 0;
187 Expression key = null;
188 if (groupBy != null) {
189 algorithm = ForEachGroup.GROUP_BY;
190 key = groupBy;
191 } else if (groupAdjacent != null) {
192 algorithm = ForEachGroup.GROUP_ADJACENT;
193 key = groupAdjacent;
194 } else if (starting != null) {
195 algorithm = ForEachGroup.GROUP_STARTING;
196 key = new PatternSponsor(starting);
197 } else if (ending != null) {
198 algorithm = ForEachGroup.GROUP_ENDING;
199 key = new PatternSponsor(ending);
200 }
201
202 Expression action = compileSequenceConstructor(exec, iterateAxis(Axis.CHILD), true);
205 if (action == null) {
206 return EmptySequence.getInstance();
208 }
209 try {
210 ForEachGroup inst = new ForEachGroup(
211 select,
212 action.simplify(getStaticContext()),
213 algorithm,
214 key,
215 collator,
216 makeSortKeys() );
217 ExpressionTool.makeParentReferences(inst);
218 return inst;
219 } catch (XPathException e) {
220 compileError(e);
221 return null;
222 }
223
224 }
225
226 }
227
228 |
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