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package liquibase.parser; |
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|
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import java.util.ArrayList; |
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import java.util.Collections; |
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import java.util.Comparator; |
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import java.util.List; |
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|
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import liquibase.exception.LiquibaseException; |
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import liquibase.exception.UnexpectedLiquibaseException; |
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import liquibase.resource.ResourceAccessor; |
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import liquibase.servicelocator.ServiceLocator; |
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|
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public class ChangeLogParserFactory { |
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|
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private static ChangeLogParserFactory instance; |
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|
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private List<ChangeLogParser> parsers; |
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private Comparator<ChangeLogParser> changelogParserComparator; |
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|
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public static void reset() { |
| 21 | 17 | instance = new ChangeLogParserFactory(); |
| 22 | 17 | } |
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|
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public static ChangeLogParserFactory getInstance() { |
| 25 | 43 | if (instance == null) { |
| 26 | 1 | instance = new ChangeLogParserFactory(); |
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} |
| 28 | 43 | return instance; |
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} |
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|
| 31 | 18 | private ChangeLogParserFactory() { |
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Class<? extends ChangeLogParser>[] classes; |
| 33 | 102 | changelogParserComparator = new Comparator<ChangeLogParser>() { |
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@Override |
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public int compare(ChangeLogParser o1, ChangeLogParser o2) { |
| 36 | 84 | return Integer.valueOf(o2.getPriority()).compareTo(o1.getPriority()); |
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} |
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}; |
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|
| 40 | 18 | parsers = new ArrayList<ChangeLogParser>(); |
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try { |
| 42 | 18 | classes = ServiceLocator.getInstance().findClasses(ChangeLogParser.class); |
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|
| 44 | 72 | for (Class<? extends ChangeLogParser> clazz : classes) { |
| 45 | 54 | register((ChangeLogParser) clazz.getConstructor().newInstance()); |
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} |
| 47 | 0 | } catch (Exception e) { |
| 48 | 0 | throw new UnexpectedLiquibaseException(e); |
| 49 | 18 | } |
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|
| 51 | 18 | } |
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|
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public List<ChangeLogParser> getParsers() { |
| 54 | 20 | return parsers; |
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} |
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|
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public ChangeLogParser getParser(String fileNameOrExtension, ResourceAccessor resourceAccessor) |
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throws LiquibaseException { |
| 59 | 13 | for (ChangeLogParser parser : parsers) { |
| 60 | 22 | if (parser.supports(fileNameOrExtension, resourceAccessor)) { |
| 61 | 12 | return parser; |
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} |
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} |
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|
| 65 | 1 | throw new LiquibaseException("Cannot find parser that supports " + fileNameOrExtension); |
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} |
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public void register(ChangeLogParser changeLogParser) { |
| 69 | 68 | parsers.add(changeLogParser); |
| 70 | 68 | Collections.sort(parsers, changelogParserComparator); |
| 71 | 68 | } |
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|
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public void unregister(ChangeLogParser changeLogParser) { |
| 74 | 3 | parsers.remove(changeLogParser); |
| 75 | 3 | } |
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} |