Field Bridge 将上传文件内容加入全文检索（转）

下面是转载hibernate search的使用文档，例子有些信息是不全的。

这里特别要注意的是加入各种bridge注解的属性里，都要加入field注解，因为不加入field注解的话，就不能进行索引，那加入bridge也就白加了。

@Entity @Indexedpublic class Meeting { @Field(index=Index.UN_TOKENIZED) @DateBridge(resolution=Resolution.MINUTE) private Date date; ... ?/** * Padding Integer bridge. * All numbers will be padded with 0 to match 5 digits * * @author Emmanuel Bernard */public class PaddedIntegerBridge implements StringBridge { private int PADDING = 5; public String objectToString(Object object) { String rawInteger = ( (Integer) object ).toString(); if (rawInteger.length() > PADDING) throw new IllegalArgumentException( "Try to pad on a number too big" ); StringBuilder paddedInteger = new StringBuilder( ); for ( int padIndex = rawInteger.length() ; padIndex < PADDING ; padIndex++ ) { paddedInteger.append('0'); } return paddedInteger.append( rawInteger ).toString(); }}

@FieldBridge(impl = PaddedIntegerBridge.class)private Integer length; ?Parameters can be passed to the Bridge implementation making it more flexible. The Bridge implementation implements a?public class PaddedIntegerBridge implements StringBridge, ParameterizedBridge { public static String PADDING_PROPERTY = "padding"; private int padding = 5; //default public void setParameterValues(Map parameters) { Object padding = parameters.get( PADDING_PROPERTY ); if (padding != null) this.padding = (Integer) padding; } public String objectToString(Object object) { String rawInteger = ( (Integer) object ).toString(); if (rawInteger.length() > padding) throw new IllegalArgumentException( "Try to pad on a number too big" ); StringBuilder paddedInteger = new StringBuilder( ); for ( int padIndex = rawInteger.length() ; padIndex < padding ; padIndex++ ) { paddedInteger.append('0'); } return paddedInteger.append( rawInteger ).toString(); }}//property@FieldBridge(impl = PaddedIntegerBridge.class, params = @Parameter(name="padding", value="10") )private Integer length;?The?public class PaddedIntegerBridge implements TwoWayStringBridge, ParameterizedBridge { public static String PADDING_PROPERTY = "padding"; private int padding = 5; //default public void setParameterValues(Map parameters) { Object padding = parameters.get( PADDING_PROPERTY ); if (padding != null) this.padding = (Integer) padding; } public String objectToString(Object object) { String rawInteger = ( (Integer) object ).toString(); if (rawInteger.length() > padding) throw new IllegalArgumentException( "Try to pad on a number too big" ); StringBuilder paddedInteger = new StringBuilder( ); for ( int padIndex = rawInteger.length() ; padIndex < padding ; padIndex++ ) { paddedInteger.append('0'); } return paddedInteger.append( rawInteger ).toString(); } public Object stringToObject(String stringValue) { return new Integer(stringValue); }}//id property@DocumentId@FieldBridge(impl = PaddedIntegerBridge.class, params = @Parameter(name="padding", value="10") private Integer id; ?It is critically important for the two-way process to be idempotent (ie object = stringToObject( objectToString( object ) ) )./** * Store the date in 3 different fields - year, month, day - to ease Range Query per * year, month or day (eg get all the elements of December for the last 5 years). * * @author Emmanuel Bernard */public class DateSplitBridge implements FieldBridge { private final static TimeZone GMT = TimeZone.getTimeZone("GMT"); public void set(String name, Object value, Document document, LuceneOptions luceneOptions) { Date date = (Date) value; Calendar cal = GregorianCalendar.getInstance(GMT); cal.setTime(date); int year = cal.get(Calendar.YEAR); int month = cal.get(Calendar.MONTH) + 1; int day = cal.get(Calendar.DAY_OF_MONTH); // set year Field field = new Field(name + ".year", String.valueOf(year), luceneOptions.getStore(), luceneOptions.getIndex(), luceneOptions.getTermVector()); field.setBoost(luceneOptions.getBoost()); document.add(field); // set month and pad it if needed field = new Field(name + ".month", month < 10 ? "0" : "" + String.valueOf(month), luceneOptions.getStore(), luceneOptions.getIndex(), luceneOptions.getTermVector()); field.setBoost(luceneOptions.getBoost()); document.add(field); // set day and pad it if needed field = new Field(name + ".day", day < 10 ? "0" : "" + String.valueOf(day), luceneOptions.getStore(), luceneOptions.getIndex(), luceneOptions.getTermVector()); field.setBoost(luceneOptions.getBoost()); document.add(field); }}//property@FieldBridge(impl = DateSplitBridge.class)private Date date; ?@Entity@Indexed@ClassBridge(name="branchnetwork", index=Index.TOKENIZED, store=Store.YES, impl = CatFieldsClassBridge.class, params = @Parameter( name="sepChar", value=" " ) )public class Department { private int id; private String network; private String branchHead; private String branch; private Integer maxEmployees ...}public class CatFieldsClassBridge implements FieldBridge, ParameterizedBridge { private String sepChar; public void setParameterValues(Map parameters) { this.sepChar = (String) parameters.get( "sepChar" ); } public void set(String name, Object value, Document document, LuceneOptions luceneOptions) { // In this particular class the name of the new field was passed // from the name field of the ClassBridge Annotation. This is not // a requirement. It just works that way in this instance. The // actual name could be supplied by hard coding it below. Department dep = (Department) value; String fieldValue1 = dep.getBranch(); if ( fieldValue1 == null ) { fieldValue1 = ""; } String fieldValue2 = dep.getNetwork(); if ( fieldValue2 == null ) { fieldValue2 = ""; } String fieldValue = fieldValue1 + sepChar + fieldValue2; Field field = new Field( name, fieldValue, luceneOptions.getStore(), luceneOptions.getIndex(), luceneOptions.getTermVector() ); field.setBoost( luceneOptions.getBoost() ); document.add( field ); }}?In this example, the particular?CatFieldsClassBridge?is applied to the?department?instance, the field bridge then concatenate both branch and network and index the concatenation.