| 1 | package org.apache.velocity.runtime.directive; |
| 2 | |
| 3 | /* |
| 4 | * Copyright 2000-2001,2004 The Apache Software Foundation. |
| 5 | * |
| 6 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 7 | * you may not use this file except in compliance with the License. |
| 8 | * You may obtain a copy of the License at |
| 9 | * |
| 10 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 11 | * |
| 12 | * Unless required by applicable law or agreed to in writing, software |
| 13 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 14 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 15 | * See the License for the specific language governing permissions and |
| 16 | * limitations under the License. |
| 17 | */ |
| 18 | |
| 19 | import java.io.Writer; |
| 20 | import java.io.IOException; |
| 21 | import java.io.BufferedReader; |
| 22 | import java.io.StringReader; |
| 23 | |
| 24 | import java.util.HashMap; |
| 25 | |
| 26 | import org.apache.velocity.context.InternalContextAdapter; |
| 27 | import org.apache.velocity.context.VMContext; |
| 28 | |
| 29 | import org.apache.velocity.runtime.visitor.VMReferenceMungeVisitor; |
| 30 | import org.apache.velocity.runtime.RuntimeServices; |
| 31 | import org.apache.velocity.runtime.parser.node.Node; |
| 32 | import org.apache.velocity.runtime.parser.Token; |
| 33 | import org.apache.velocity.runtime.parser.ParserTreeConstants; |
| 34 | import org.apache.velocity.runtime.parser.node.SimpleNode; |
| 35 | import org.apache.velocity.util.StringUtils; |
| 36 | |
| 37 | import org.apache.velocity.exception.MethodInvocationException; |
| 38 | |
| 39 | /** |
| 40 | * VelocimacroProxy.java |
| 41 | * |
| 42 | * a proxy Directive-derived object to fit with the current directive system |
| 43 | * |
| 44 | * @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a> |
| 45 | * @version $Id: VelocimacroProxy.java,v 1.27.4.1 2004/03/03 23:22:56 geirm Exp $ |
| 46 | */ |
| 47 | public class VelocimacroProxy extends Directive |
| 48 | { |
| 49 | private String macroName = ""; |
| 50 | private String macroBody = ""; |
| 51 | private String[] argArray = null; |
| 52 | private SimpleNode nodeTree = null; |
| 53 | private int numMacroArgs = 0; |
| 54 | private String namespace = ""; |
| 55 | |
| 56 | private boolean init = false; |
| 57 | private String[] callingArgs; |
| 58 | private int[] callingArgTypes; |
| 59 | private HashMap proxyArgHash = new HashMap(); |
| 60 | |
| 61 | |
| 62 | /** |
| 63 | * Return name of this Velocimacro. |
| 64 | */ |
| 65 | public String getName() |
| 66 | { |
| 67 | return macroName; |
| 68 | } |
| 69 | |
| 70 | /** |
| 71 | * Velocimacros are always LINE |
| 72 | * type directives. |
| 73 | */ |
| 74 | public int getType() |
| 75 | { |
| 76 | return LINE; |
| 77 | } |
| 78 | |
| 79 | /** |
| 80 | * sets the directive name of this VM |
| 81 | */ |
| 82 | public void setName( String name ) |
| 83 | { |
| 84 | macroName = name; |
| 85 | } |
| 86 | |
| 87 | /** |
| 88 | * sets the array of arguments specified in the macro definition |
| 89 | */ |
| 90 | public void setArgArray( String [] arr ) |
| 91 | { |
| 92 | argArray = arr; |
| 93 | |
| 94 | /* |
| 95 | * get the arg count from the arg array. remember that the arg array |
| 96 | * has the macro name as it's 0th element |
| 97 | */ |
| 98 | |
| 99 | numMacroArgs = argArray.length - 1; |
| 100 | } |
| 101 | |
| 102 | public void setNodeTree( SimpleNode tree ) |
| 103 | { |
| 104 | nodeTree = tree; |
| 105 | } |
| 106 | |
| 107 | /** |
| 108 | * returns the number of ars needed for this VM |
| 109 | */ |
| 110 | public int getNumArgs() |
| 111 | { |
| 112 | return numMacroArgs; |
| 113 | } |
| 114 | |
| 115 | /** |
| 116 | * Sets the orignal macro body. This is simply the cat of the macroArray, but the |
| 117 | * Macro object creates this once during parsing, and everyone shares it. |
| 118 | * Note : it must not be modified. |
| 119 | */ |
| 120 | public void setMacrobody( String mb ) |
| 121 | { |
| 122 | macroBody = mb; |
| 123 | } |
| 124 | |
| 125 | public void setNamespace( String ns ) |
| 126 | { |
| 127 | this.namespace = ns; |
| 128 | } |
| 129 | |
| 130 | /** |
| 131 | * Renders the macro using the context |
| 132 | */ |
| 133 | public boolean render( InternalContextAdapter context, Writer writer, Node node) |
| 134 | throws IOException, MethodInvocationException |
| 135 | { |
| 136 | try |
| 137 | { |
| 138 | /* |
| 139 | * it's possible the tree hasn't been parsed yet, so get |
| 140 | * the VMManager to parse and init it |
| 141 | */ |
| 142 | |
| 143 | if (nodeTree != null) |
| 144 | { |
| 145 | if ( !init ) |
| 146 | { |
| 147 | nodeTree.init( context, rsvc); |
| 148 | init = true; |
| 149 | } |
| 150 | |
| 151 | /* |
| 152 | * wrap the current context and add the VMProxyArg objects |
| 153 | */ |
| 154 | |
| 155 | VMContext vmc = new VMContext( context, rsvc ); |
| 156 | |
| 157 | for( int i = 1; i < argArray.length; i++) |
| 158 | { |
| 159 | /* |
| 160 | * we can do this as VMProxyArgs don't change state. They change |
| 161 | * the context. |
| 162 | */ |
| 163 | |
| 164 | VMProxyArg arg = (VMProxyArg) proxyArgHash.get( argArray[i] ); |
| 165 | vmc.addVMProxyArg( arg ); |
| 166 | } |
| 167 | |
| 168 | /* |
| 169 | * now render the VM |
| 170 | */ |
| 171 | |
| 172 | nodeTree.render( vmc, writer ); |
| 173 | } |
| 174 | else |
| 175 | { |
| 176 | rsvc.error( "VM error : " + macroName + ". Null AST"); |
| 177 | } |
| 178 | } |
| 179 | catch ( Exception e ) |
| 180 | { |
| 181 | /* |
| 182 | * if it's a MIE, it came from the render.... throw it... |
| 183 | */ |
| 184 | |
| 185 | if ( e instanceof MethodInvocationException) |
| 186 | { |
| 187 | throw (MethodInvocationException) e; |
| 188 | } |
| 189 | |
| 190 | rsvc.error("VelocimacroProxy.render() : exception VM = #" + macroName + |
| 191 | "() : " + StringUtils.stackTrace(e)); |
| 192 | } |
| 193 | |
| 194 | return true; |
| 195 | } |
| 196 | |
| 197 | /** |
| 198 | * The major meat of VelocimacroProxy, init() checks the # of arguments, patches the |
| 199 | * macro body, renders the macro into an AST, and then inits the AST, so it is ready |
| 200 | * for quick rendering. Note that this is only AST dependant stuff. Not context. |
| 201 | */ |
| 202 | public void init( RuntimeServices rs, InternalContextAdapter context, Node node) |
| 203 | throws Exception |
| 204 | { |
| 205 | super.init( rs, context, node ); |
| 206 | |
| 207 | /* |
| 208 | * how many args did we get? |
| 209 | */ |
| 210 | |
| 211 | int i = node.jjtGetNumChildren(); |
| 212 | |
| 213 | /* |
| 214 | * right number of args? |
| 215 | */ |
| 216 | |
| 217 | if ( getNumArgs() != i ) |
| 218 | { |
| 219 | rsvc.error("VM #" + macroName + ": error : too " |
| 220 | + ( (getNumArgs() > i) ? "few" : "many") + " arguments to macro. Wanted " |
| 221 | + getNumArgs() + " got " + i ); |
| 222 | |
| 223 | return; |
| 224 | } |
| 225 | |
| 226 | /* |
| 227 | * get the argument list to the instance use of the VM |
| 228 | */ |
| 229 | |
| 230 | callingArgs = getArgArray( node ); |
| 231 | |
| 232 | /* |
| 233 | * now proxy each arg in the context |
| 234 | */ |
| 235 | |
| 236 | setupMacro( callingArgs, callingArgTypes ); |
| 237 | return; |
| 238 | } |
| 239 | |
| 240 | /** |
| 241 | * basic VM setup. Sets up the proxy args for this |
| 242 | * use, and parses the tree |
| 243 | */ |
| 244 | public boolean setupMacro( String[] callArgs, int[] callArgTypes ) |
| 245 | { |
| 246 | setupProxyArgs( callArgs, callArgTypes ); |
| 247 | parseTree( callArgs ); |
| 248 | |
| 249 | return true; |
| 250 | } |
| 251 | |
| 252 | /** |
| 253 | * parses the macro. We need to do this here, at init time, or else |
| 254 | * the local-scope template feature is hard to get to work :) |
| 255 | */ |
| 256 | private void parseTree( String[] callArgs ) |
| 257 | { |
| 258 | try |
| 259 | { |
| 260 | BufferedReader br = new BufferedReader( new StringReader( macroBody ) ); |
| 261 | |
| 262 | /* |
| 263 | * now parse the macro - and don't dump the namespace |
| 264 | */ |
| 265 | |
| 266 | nodeTree = rsvc.parse( br, namespace, false ); |
| 267 | |
| 268 | /* |
| 269 | * now, to make null references render as proper schmoo |
| 270 | * we need to tweak the tree and change the literal of |
| 271 | * the appropriate references |
| 272 | * |
| 273 | * we only do this at init time, so it's the overhead |
| 274 | * is irrelevant |
| 275 | */ |
| 276 | |
| 277 | HashMap hm = new HashMap(); |
| 278 | |
| 279 | for( int i = 1; i < argArray.length; i++) |
| 280 | { |
| 281 | String arg = callArgs[i-1]; |
| 282 | |
| 283 | /* |
| 284 | * if the calling arg is indeed a reference |
| 285 | * then we add to the map. We ignore other |
| 286 | * stuff |
| 287 | */ |
| 288 | |
| 289 | if (arg.charAt(0) == '$') |
| 290 | { |
| 291 | hm.put( argArray[i], arg ); |
| 292 | } |
| 293 | } |
| 294 | |
| 295 | /* |
| 296 | * now make one of our reference-munging visitor, and |
| 297 | * let 'er rip |
| 298 | */ |
| 299 | |
| 300 | VMReferenceMungeVisitor v = new VMReferenceMungeVisitor( hm ); |
| 301 | nodeTree.jjtAccept( v, null ); |
| 302 | } |
| 303 | catch ( Exception e ) |
| 304 | { |
| 305 | rsvc.error("VelocimacroManager.parseTree() : exception " + macroName + |
| 306 | " : " + StringUtils.stackTrace(e)); |
| 307 | } |
| 308 | } |
| 309 | |
| 310 | private void setupProxyArgs( String[] callArgs, int [] callArgTypes ) |
| 311 | { |
| 312 | /* |
| 313 | * for each of the args, make a ProxyArg |
| 314 | */ |
| 315 | |
| 316 | for( int i = 1; i < argArray.length; i++) |
| 317 | { |
| 318 | VMProxyArg arg = new VMProxyArg( rsvc, argArray[i], callArgs[i-1], callArgTypes[i-1] ); |
| 319 | proxyArgHash.put( argArray[i], arg ); |
| 320 | } |
| 321 | } |
| 322 | |
| 323 | /** |
| 324 | * gets the args to the VM from the instance-use AST |
| 325 | */ |
| 326 | private String[] getArgArray( Node node ) |
| 327 | { |
| 328 | int numArgs = node.jjtGetNumChildren(); |
| 329 | |
| 330 | String args[] = new String[ numArgs ]; |
| 331 | callingArgTypes = new int[numArgs]; |
| 332 | |
| 333 | /* |
| 334 | * eat the args |
| 335 | */ |
| 336 | int i = 0; |
| 337 | Token t = null; |
| 338 | Token tLast = null; |
| 339 | |
| 340 | while( i < numArgs ) |
| 341 | { |
| 342 | args[i] = ""; |
| 343 | /* |
| 344 | * we want string literalss to lose the quotes. #foo( "blargh" ) should have 'blargh' patched |
| 345 | * into macro body. So for each arg in the use-instance, treat the stringlierals specially... |
| 346 | */ |
| 347 | |
| 348 | callingArgTypes[i] = node.jjtGetChild(i).getType(); |
| 349 | |
| 350 | |
| 351 | if (false && node.jjtGetChild(i).getType() == ParserTreeConstants.JJTSTRINGLITERAL ) |
| 352 | { |
| 353 | args[i] += node.jjtGetChild(i).getFirstToken().image.substring(1, node.jjtGetChild(i).getFirstToken().image.length() - 1); |
| 354 | } |
| 355 | else |
| 356 | { |
| 357 | /* |
| 358 | * just wander down the token list, concatenating everything together |
| 359 | */ |
| 360 | t = node.jjtGetChild(i).getFirstToken(); |
| 361 | tLast = node.jjtGetChild(i).getLastToken(); |
| 362 | |
| 363 | while( t != tLast ) |
| 364 | { |
| 365 | args[i] += t.image; |
| 366 | t = t.next; |
| 367 | } |
| 368 | |
| 369 | /* |
| 370 | * don't forget the last one... :) |
| 371 | */ |
| 372 | args[i] += t.image; |
| 373 | } |
| 374 | i++; |
| 375 | } |
| 376 | return args; |
| 377 | } |
| 378 | } |
| 379 | |
| 380 | |
| 381 | |
| 382 | |
| 383 | |
| 384 | |
| 385 | |
| 386 | |
| 387 | |
| 388 | |