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1
4 package gnu.kawa.xml;
5 import gnu.bytecode.*;
6 import gnu.mapping.*;
7 import gnu.expr.*;
8 import gnu.xml.*;
9 import gnu.lists.*;
10
11 public abstract class NodeConstructor extends MethodProc
12 implements Inlineable
13 {
14 public abstract void compileToNode (ApplyExp exp, Compilation comp,
15 ConsumerTarget target);
16
17 public static XMLFilter pushNodeConsumer (Consumer out)
18 {
19 if (out instanceof XMLFilter)
20 return (XMLFilter) out;
21 else
22 return new XMLFilter(new NodeTree());
23 }
24
25 public static void popNodeConsumer (Consumer saved, Consumer current)
26 {
27 if (saved != current)
28 saved.writeObject(current instanceof XMLFilter
29 ? (Object  ) KNode.make((NodeTree) ((XMLFilter) current).out)
30 : (Object ) current);
31 }
32
33 public static XMLFilter pushNodeContext (CallContext ctx)
34 {
35 Consumer out = ctx.consumer;
36 if (out instanceof XMLFilter)
37 return (XMLFilter) out;
38 else
39 {
40 XMLFilter filter = new XMLFilter(new NodeTree());
41 ctx.consumer = filter;
42 return filter;
43 }
44 }
45
46 public static void popNodeContext (Consumer saved, CallContext ctx)
47 {
48 Object current = ctx.consumer;
49 if (saved != current)
50 {
51 if (current instanceof XMLFilter)
52 current = KNode.make((NodeTree) ((XMLFilter) current).out);
53 saved.writeObject(current);
54 ctx.consumer = saved;
55 }
56 }
57
58 public static void compileChild (Expression arg,
59 Compilation comp, ConsumerTarget target)
60 {
61 if (arg instanceof ApplyExp)
62 {
63 ApplyExp app = (ApplyExp) arg;
64 Expression func = app.getFunction();
65 if (func instanceof QuoteExp)
66 {
67 Object proc = ((QuoteExp) func).getValue();
68 if (proc instanceof NodeConstructor)
69 {
70 ((NodeConstructor) proc).compileToNode(app, comp, target);
71 return;
72 }
73 }
74 }
75 arg.compileWithPosition(comp, target);
76 }
77
78
81 public static void compileUsingNodeTree(Expression exp,
82 Compilation comp, Target target)
83 {
84 Method makeMethod = typeNodeConstructor.getDeclaredMethod("makeNode", 0);
85 Method makeKNodeMethod = typeNodeConstructor.getDeclaredMethod("finishNode", 1);
86 ConsumerTarget.compileUsingConsumer(exp, comp, target,
87 makeMethod, makeKNodeMethod);
88 }
89
90 public static XMLFilter makeNode ()
91 {
92 return new XMLFilter(new NodeTree());
93 }
94
95 public static KNode finishNode (XMLFilter filter)
96 {
97 return KNode.make((NodeTree) filter.out);
98 }
99
100 public void compile (ApplyExp exp, Compilation comp, Target target)
101 {
102 if (target instanceof IgnoreTarget)
103 ApplyExp.compile(exp, comp, target);
104 else if (! (target instanceof ConsumerTarget))
105 compileUsingNodeTree(exp, comp, target);
106 else
107 {
108 ConsumerTarget ctarget = (ConsumerTarget) target;
109 Variable cvar = ctarget.getConsumerVariable();
110 Type ctype = cvar.getType();
111 if (ctype.isSubtype(typeXMLFilter))
112 compileToNode(exp, comp, ctarget);
113 else
114 {
115 Expression[] args = exp.getArgs();
116 int nargs = args.length;
117 CodeAttr code = comp.getCode();
118 Scope scope = code.pushScope();
119 Variable saved
120 = scope.addVariable(code, Compilation.typeConsumer, null);
121 code.emitLoad(cvar);
122 code.emitStore(saved);
123 if (ctarget.isContextTarget())
124 {
125 comp.loadCallContext();
126 code.emitInvokeStatic(pushNodeContextMethod);
127 }
128 else
129 {
130 code.emitLoad(cvar);
131 code.emitInvokeStatic(pushNodeConsumerMethod);
132 }
133 code.emitStore(cvar);
134 code.emitTryStart(true, Type.void_type);
135 Type saveType = cvar.getType();
136 cvar.setType(typeXMLFilter);
139 compileToNode(exp, comp, ctarget);
140 cvar.setType(saveType);
141 code.emitTryEnd();
142 code.emitFinallyStart();
143 code.emitLoad(saved);
144 if (ctarget.isContextTarget())
145 {
146 comp.loadCallContext();
147 code.emitInvokeStatic(popNodeContextMethod);
148 }
149 else
150 {
151 code.emitLoad(cvar);
152 code.emitInvokeStatic(popNodeConsumerMethod);
153 }
154 code.emitLoad(saved);
155 code.emitStore(cvar);
156 code.emitFinallyEnd();
157 code.emitTryCatchEnd();
158 code.popScope();
159 }
160 }
161 }
162
163 public Type getReturnType (Expression[] args)
164 {
165 return Compilation.typeObject;
166 }
167
168 static final ClassType typeXMLFilter
169 = ClassType.make("gnu.xml.XMLFilter");
170 static final ClassType typeKNode
171 = ClassType.make("gnu.kawa.xml.KNode");
172 static final ClassType typeNodeConstructor
173 = ClassType.make("gnu.kawa.xml.NodeConstructor");
174 static final Method pushNodeContextMethod
175 = typeNodeConstructor.getDeclaredMethod("pushNodeContext", 1);
176 static final Method popNodeContextMethod
177 = typeNodeConstructor.getDeclaredMethod("popNodeContext", 2);
178 static final Method pushNodeConsumerMethod
179 = typeNodeConstructor.getDeclaredMethod("pushNodeConsumer", 1);
180 static final Method popNodeConsumerMethod
181 = typeNodeConstructor.getDeclaredMethod("popNodeConsumer", 2);
182 }
183 |
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