G(arbage) C(ollected) X(Query) Engine: stringconstexpression.cpp Source File

00001 
00002 /*
00003  | Author: Michael Schmidt;
00004  |         Gunnar Jehl
00005  |
00006  | ************************* SOFTWARE LICENSE AGREEMENT ***********************
00007  | This source code is published under the BSD License.
00008  |
00009  | See file 'LICENSE.txt' that comes with this distribution or
00010  | http://dbis.informatik.uni-freiburg.de/index.php?project=GCX/license.php
00011  | for the full license agreement.
00012  |
00013  | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
00014  | AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
00015  | IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
00016  | ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
00017  | LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
00018  | CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
00019  | SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
00020  | INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
00021  | CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
00022  | ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
00023  | POSSIBILITY OF SUCH DAMAGE.
00024  | ****************************************************************************
00025 */
00026 
00035 #include "stringconstexpression.h"
00036 
00037 StringConstExpression::
00038 StringConstExpression(const char *_str):ConstExpression(et_stringconst) {
00039     // we replace special signs, namely: < -> &lt and > -> &gt;
00040     ostringstream s;
00041 
00042     for (unsigned i = 0; i < strlen(_str); i++) {
00043         if (_str[i] == '<') {
00044             s << "&lt;";
00045         } else if (_str[i] == '>') {
00046             s << "&gt;";
00047         } else {
00048             s << _str[i];
00049         }
00050     }
00051     str = strdup(s.str().c_str());
00052     delete[]_str;
00053 }
00054 
00055 StringConstExpression::~StringConstExpression() {
00056     free((char *) str);
00057 }
00058 
00059 void StringConstExpression::print(OutputStream & dos) const {
00060     dos << "\"" << str << "\"";
00061 }
00062 
00063 void StringConstExpression::eval(OutputStream & eos, Environment * env,
00064                                  unsigned modus) {
00065 
00066     switch (modus) {
00067 
00068         case EVAL_QUERY:
00069             eos << str;
00070             break;
00071 
00072         case EVAL_SIGNOFF:
00073             break;
00074 
00075         default:
00076             throw
00077                 RuntimeException
00078                 ("StringConstExpression: Illegal Evaluation Mode",
00079                  eid_runtime_illegalmode);
00080             break;
00081     }
00082 }
00083 
00084 Value *StringConstExpression::getNextValue() {
00085     if (initial) {
00086         initial = false;
00087         cur_val.setStrVal(strdup(str));
00088         return &cur_val;
00089     } else {
00090         initial = true;
00091         return NULL;
00092     }
00093 }