RecordIterator


1   /*
2    * $Id: RecordIterator.java 5462 2005-08-05 18:35:48Z jonesde $
3    *
4    * Copyright (c) 2001-2005 The Open For Business Project - www.ofbiz.org
5    *
6    * Permission is hereby granted, free of charge, to any person obtaining a
7    * copy of this software and associated documentation files (the "Software"),
8    * to deal in the Software without restriction, including without limitation
9    * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10   * and/or sell copies of the Software, and to permit persons to whom the
11   * Software is furnished to do so, subject to the following conditions:
12   *
13   * The above copyright notice and this permission notice shall be included
14   * in all copies or substantial portions of the Software.
15   *
16   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17   * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
19   * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
20   * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT
21   * OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR
22   * THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23   *
24   */
25  package org.ofbiz.datafile;
26  
27  
28  import java.io.BufferedReader  ;
29  import java.io.IOException  ;
30  import java.io.InputStream  ;
31  import java.io.InputStreamReader  ;
32  import java.net.URL  ;
33  import java.util.Stack  ;
34  
35  
36  /**
37   *  Record Iterator for reading large files
38   *
39   * @author     <a HREF="mailto:jonesde@ofbiz.org">David E. Jones</a>
40   * @version    $Rev: 5462 $
41   * @since      3.0
42   */
43  
44  public class RecordIterator {
45      
46      public static final String   module = RecordIterator.class.getName();
47  
48      protected BufferedReader   br;
49      protected ModelDataFile modelDataFile;
50      protected InputStream   dataFileStream;
51      protected boolean closed = false;
52      protected String   locationInfo;
53  
54      protected int nextLineNum = 0;
55      protected String   curLine = null;
56      protected Record curRecord = null;
57      protected String   nextLine = null;
58      protected Record nextRecord = null;
59      
60      public RecordIterator(URL   fileUrl, ModelDataFile modelDataFile) throws DataFileException {
61          this.modelDataFile = modelDataFile;
62  
63          InputStream   urlStream = null;
64          try {
65              urlStream = fileUrl.openStream();
66          } catch (IOException   e) {
67              throw new DataFileException("Error open URL: " + fileUrl.toString(), e);
68          }
69          this.setupStream(urlStream, fileUrl.toString());
70      }
71      
72      public RecordIterator(InputStream   dataFileStream, ModelDataFile modelDataFile, String   locationInfo) throws DataFileException {
73          this.modelDataFile = modelDataFile;
74          this.setupStream(dataFileStream, locationInfo);
75      }
76      
77      protected void setupStream(InputStream   dataFileStream, String   locationInfo) throws DataFileException {
78          this.locationInfo = locationInfo;
79          this.dataFileStream = dataFileStream;
80          try {
81              this.br = new BufferedReader  (new InputStreamReader  (dataFileStream, "UTF-8"));
82          } catch(Exception   e) {
83              throw new DataFileException("UTF-8 is not supported");
84          }
85  
86          // get the line seeded
87          this.getNextLine();
88      }
89      
90      protected boolean getNextLine() throws DataFileException {
91          this.nextLine = null;
92          this.nextRecord = null;
93          
94          boolean isFixedRecord = ModelDataFile.SEP_FIXED_RECORD.equals(modelDataFile.separatorStyle);
95          boolean isFixedLength = ModelDataFile.SEP_FIXED_LENGTH.equals(modelDataFile.separatorStyle);
96          boolean isDelimited = ModelDataFile.SEP_DELIMITED.equals(modelDataFile.separatorStyle);
97          // if (Debug.infoOn()) Debug.logInfo("[DataFile.readDataFile] separatorStyle is " + modelDataFile.separatorStyle + ", isFixedRecord: " + isFixedRecord, module);
98  
99          if (isFixedRecord) {
100             if (modelDataFile.recordLength <= 0) {
101                 throw new DataFileException("Cannot read a fixed record length file if no record length is specified");
102             }
103 
104             try {
105                 char[] charData = new char[modelDataFile.recordLength + 1];
106 
107                 // if (Debug.infoOn()) Debug.logInfo("[DataFile.readDataFile] reading line " + lineNum + " from position " + (lineNum-1)*modelDataFile.recordLength + ", length is " + modelDataFile.recordLength, module);
108                 if (br.read(charData, 0, modelDataFile.recordLength) == -1) {
109                     nextLine = null;
110                     // Debug.logInfo("[DataFile.readDataFile] found end of file, got -1", module);
111                 } else {
112                     nextLine = new String  (charData);
113                     // if (Debug.infoOn()) Debug.logInfo("[DataFile.readDataFile] read line " + lineNum + " line is: \"" + line + "\"", module);
114                 }
115             } catch (IOException   e) {
116                 throw new DataFileException("Error reading line #" + nextLineNum + " (index " + (nextLineNum - 1) * modelDataFile.recordLength + " length " +
117                         modelDataFile.recordLength + ") from location: " + locationInfo, e);
118             }
119         } else {
120             try {
121                 nextLine = br.readLine();
122             } catch (IOException   e) {
123                 throw new DataFileException("Error reading line #" + nextLineNum + " from location: " + locationInfo, e);
124             }
125         }
126         
127         if (nextLine != null) {
128             nextLineNum++;
129             ModelRecord modelRecord = findModelForLine(nextLine, nextLineNum, modelDataFile);
130             if (isDelimited) {
131                 this.nextRecord = Record.createDelimitedRecord(nextLine, nextLineNum, modelRecord, modelDataFile.delimiter);
132             } else {
133                 this.nextRecord = Record.createRecord(nextLine, nextLineNum, modelRecord);
134             }
135             return true;
136         } else {
137             this.close();
138             return false;
139         }
140     }
141     
142     public int getCurrentLineNumber() {
143         return this.nextLineNum - 1;
144     }
145     
146     public boolean hasNext() {
147         return nextLine != null;
148     }
149     
150     public Record next() throws DataFileException {
151         if (!hasNext()) {
152             return null;
153         }
154         
155         if (ModelDataFile.SEP_DELIMITED.equals(modelDataFile.separatorStyle) || ModelDataFile.SEP_FIXED_RECORD.equals(modelDataFile.separatorStyle) || ModelDataFile.SEP_FIXED_LENGTH.equals(modelDataFile.separatorStyle)) {
156             boolean isFixedRecord = ModelDataFile.SEP_FIXED_RECORD.equals(modelDataFile.separatorStyle);
157             // if (Debug.infoOn()) Debug.logInfo("[DataFile.readDataFile] separatorStyle is " + modelDataFile.separatorStyle + ", isFixedRecord: " + isFixedRecord, module);
158             
159             // advance the line (we have already checked to make sure there is a next line
160             this.curLine = this.nextLine;
161             this.curRecord = this.nextRecord;
162             
163             // get a new next line
164             this.getNextLine();
165 
166             // first check to see if the file type has a line size, and if so if this line complies
167             if (!isFixedRecord && modelDataFile.recordLength > 0 && curLine.length() != modelDataFile.recordLength) {
168                 throw new DataFileException("Line number " + this.getCurrentLineNumber() + " was not the expected length; expected: " + modelDataFile.recordLength + ", got: " + curLine.length());
169             }
170 
171             // if this record has children, put it on the parentStack and get/check the children now
172             if (this.curRecord.getModelRecord().childRecords.size() > 0) {
173                 Stack   parentStack = new Stack  ();
174                 parentStack.push(curRecord);
175                 
176                 while (this.nextRecord != null && this.nextRecord.getModelRecord().parentRecord != null) {
177                     // if parent equals top parent on stack, add to that parents child list, otherwise pop off parent and try again
178                     Record parentRecord = null;
179 
180                     while (parentStack.size() > 0) {
181                         parentRecord = (Record) parentStack.peek();
182                         if (parentRecord.recordName.equals(this.nextRecord.getModelRecord().parentName)) {
183                             break;
184                         } else {
185                             parentStack.pop();
186                             parentRecord = null;
187                         }
188                     }
189 
190                     if (parentRecord == null) {
191                         throw new DataFileException("Expected Parent Record not found for line " + this.getCurrentLineNumber() + "; record name of expected parent is " + this.nextRecord.getModelRecord().parentName);
192                     }
193 
194                     parentRecord.addChildRecord(this.nextRecord);
195                     
196                     // if the child record we just added is also a parent, push it onto the stack
197                     if (this.nextRecord.getModelRecord().childRecords.size() > 0) {
198                         parentStack.push(this.nextRecord);
199                     }
200                         
201                     // if it can't find a next line it will nextRecord will be null and the loop will break out
202                     this.getNextLine();
203                 }
204             }
205         } else {
206             throw new DataFileException("Separator style " + modelDataFile.separatorStyle + " not recognized.");
207         }
208         
209         return curRecord;
210     }
211 
212     public void close() throws DataFileException {
213         if (this.closed) {
214             return;
215         }
216         try {
217             this.br.close(); // this should also close the stream
218             this.closed = true;
219         } catch (IOException   e) {
220             throw new DataFileException("Error closing data file input stream", e);
221         }
222     }
223 
224 
225     /** Searches through the record models to find one with a matching type-code, if no type-code exists that model will always be used if it gets to it
226      * @param line
227      * @param lineNum
228      * @param modelDataFile
229      * @throws DataFileException Exception thown for various errors, generally has a nested exception
230      * @return
231      */
232     protected static ModelRecord findModelForLine(String   line, int lineNum, ModelDataFile modelDataFile) throws DataFileException {
233         // if (Debug.infoOn()) Debug.logInfo("[DataFile.findModelForLine] line: " + line, module);
234         ModelRecord modelRecord = null;
235 
236         for (int i = 0; i < modelDataFile.records.size(); i++) {
237             ModelRecord curModelRecord = (ModelRecord) modelDataFile.records.get(i);
238 
239             if (curModelRecord.tcPosition < 0) {
240                 modelRecord = curModelRecord;
241                 break;
242             }
243 
244             String   typeCode = line.substring(curModelRecord.tcPosition, curModelRecord.tcPosition + curModelRecord.tcLength);
245 
246             // try to match with a single typecode
247             if (curModelRecord.typeCode.length() > 0) {
248                 // if (Debug.infoOn()) Debug.logInfo("[DataFile.findModelForLine] Doing plain typecode match - code=" + curModelRecord.typeCode + ", filelinecode=" + typeCode, module);
249                 if (typeCode != null && typeCode.equals(curModelRecord.typeCode)) {
250                     modelRecord = curModelRecord;
251                     break;
252                 }
253             } // try to match a ranged typecode (tcMin <= typeCode <= tcMax)
254             else if (curModelRecord.tcMin.length() > 0 || curModelRecord.tcMax.length() > 0) {
255                 if (curModelRecord.tcIsNum) {
256                     // if (Debug.infoOn()) Debug.logInfo("[DataFile.findModelForLine] Doing ranged number typecode match - minNum=" + curModelRecord.tcMinNum + ", maxNum=" + curModelRecord.tcMaxNum + ", filelinecode=" + typeCode, module);
257                     long typeCodeNum = Long.parseLong(typeCode);
258 
259                     if ((curModelRecord.tcMinNum < 0 || typeCodeNum >= curModelRecord.tcMinNum) &&
260                             (curModelRecord.tcMaxNum < 0 || typeCodeNum <= curModelRecord.tcMaxNum)) {
261                         modelRecord = curModelRecord;
262                         break;
263                     }
264                 } else {
265                     // if (Debug.infoOn()) Debug.logInfo("[DataFile.findModelForLine] Doing ranged String typecode match - min=" + curModelRecord.tcMin + ", max=" + curModelRecord.tcMax + ", filelinecode=" + typeCode, module);
266                     if ((typeCode.compareTo(curModelRecord.tcMin) >= 0) &&
267                             (typeCode.compareTo(curModelRecord.tcMax) <= 0)) {
268                         modelRecord = curModelRecord;
269                         break;
270                     }
271                 }
272             }
273         }
274         
275         if (modelRecord == null) {
276             throw new DataFileException("Could not find record definition for line " + lineNum + "; first bytes: " +
277                     line.substring(0, (line.length() > 5) ? 5 : line.length()));
278         }
279         // if (Debug.infoOn()) Debug.logInfo("[DataFile.findModelForLine] Got record model named " + modelRecord.name, module);
280         return modelRecord;
281     }
282 }
283 
284
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