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postgis依賴
org.geotools gt-main 27.2 org.geotools gt-jdbc-postgis 27.2 創建連接JDBCDataStore
Map params = Map.of( PostgisNGDataStoreFactory.HOST.key, host, PostgisNGDataStoreFactory.PORT.key, port, PostgisNGDataStoreFactory.DATABASE.key, database, PostgisNGDataStoreFactory.SCHEMA.key, schema, PostgisNGDataStoreFactory.USER.key, user, PostgisNGDataStoreFactory.PASSWD.key, passwd, PostgisNGDataStoreFactory.DBTYPE.key, dbtype);JDBCDataStore jdbcDataStore = (JDBCDataStore)DataStoreFinder.getDataStore(params); JDBCDataStore連接參數
| Parameter | Description |
|---|---|
| dbtype | Must be the string postgis |
| host | Machine name or IP address to connect to |
| port | Port number to connect to, default 5432 |
| schema | The database schema to access |
| database | The database to connect to |
| user | User name |
| passwd | Password |
| loose bbox | Flag controlling loose bbox comparisons, default is true |
| preparedStatements | Flag controlling whether prepared statements are used, default is false |
| encode functions | Flag controlling if some common functions can be encoded into their SQL equivalent |
連接池參數
| Parameter | Description |
|---|---|
| max connections | Maximum number of connection the pool will hold at any time, default is 10 |
| min connections | Minimum number of connection the pool will hold at any time, default is 1 |
| connection timeout | Maximum number of second the pool will wait when trying to obtain a connection, default is 20 seconds |
| validate connections | Flag controlling if the pool should validate connections when a new connection is obtained |
| Max open prepared statements | Maximum number of prepared statements kept open and cached for each connection in the pool. Set to 0 to have unbounded caching, -1 to disable |
| Test while idle | Periodically test if the connections are still valid also while idle in the pool |
| Time between evictor runs | Number of seconds between idle object evictor runs. The default value is 300 seconds. |
| Min evictable time | Number of seconds a connection needs to stay idle before the evictor starts to consider closing it |
| Evictor tests per run | Number of connections checked by the idle connection evictor for each of its runs. The default value is 3 connections. |
過濾器-Filter
使用過濾器來定義要對其進行操作的Feature集合。過濾器也可以組合成一個操作集合使用。簡單說，過濾器相當于SQL語句的WHERE子句中存在的信息。Filter有多個子類，實現了許多類型的過濾器，包括簡單的屬性比較和空間查詢。
// 普通字段FilterFactory ff = CommonFactoryFinder.getFilterFactory();/** * field 字段名 * value 條件值 * geometry 條件幾何體 * * * matchCase 是否區分大小寫，默認true-區分 * MatchAction(實現MultiValuedFilter的會有)，匹配邏輯 * MatchAction.ANY-任何一個滿足，默認值 * MatchAction.ALL-全部滿足 * MatchAction.ONE-只有一個滿足 * */PropertyIsEqualTo equal = ff.equal(ff.property(field), ff.literal(value), true);//等于PropertyIsLike like = ff.like(ff.property(field), "%keywords%");//模糊匹配PropertyIsNotEqualTo notEqualTo = ff.notEqual(ff.property(field), ff.literal(value));//不等于PropertyIsNull aNull = ff.isNull(ff.property(field));//nullPropertyIsGreaterThan greater = ff.greater(ff.property(field), ff.literal(value));// 大于PropertyIsGreaterThanOrEqualTo greaterOrEqual = ff.greaterOrEqual(ff.property(field), ff.literal(value));// 大于等于PropertyIsLessThan less = ff.less(ff.property(field), ff.literal(value));//小于PropertyIsLessThanOrEqualTo lessOrEqual = ff.lessOrEqual(ff.property(field), ff.literal(value));//小于等于PropertyIsBetween between = ff.between(ff.property(field), ff.literal(value), ff.literal(value));//在...之間During during = ff.during(ff.property(field), ff.literal(value));//在時間期間Before before = ff.before(ff.property(field), ff.literal(value));//在時間之前After after = ff.after(ff.property(field), ff.literal(value));//在時間之后// Geometry字段FilterFactory2 ff2 = CommonFactoryFinder.getFilterFactory2();Beyond beyond = ff2.beyond(ff2.property(featureSource.schema.geometryDescriptor.localName), ff2.literal(geometry), 100.0, Units.METRE.name);// 圖層幾何字段超出給定幾何100米距離的Contains contains = ff2.contains(ff2.property(featureSource.schema.geometryDescriptor.localName), ff2.literal(geometry));// 圖層幾何字段包含給定幾何Within within = ff2.within(ff2.property(featureSource.schema.geometryDescriptor.localName), ff2.literal(geometry));// 圖層幾何字段被給定幾何包含Intersects intersects = ff2.intersects(ff2.property(featureSource.schema.geometryDescriptor.localName), ff2.literal(geometry));// 圖層幾何字段與給定幾何相交Disjoint disjoint = ff2.disjoint(ff2.property(featureSource.schema.geometryDescriptor.localName), ff2.literal(geometry));// 圖層幾何字段與給定幾何不相交Touches touches = ff2.touches(ff2.property(featureSource.schema.geometryDescriptor.localName), ff2.literal(geometry));// 圖層幾何字段與給定幾何相切// filter集合的邏輯關系，and并，or或，not非And and = ff.and(List.of(equal,like,beyond));//Or or = ff.or(List.of(notEqualTo,greater,contains));Not not = ff.not(during);// Function的實現類具體實現函數，name-函數名，例如：min,strReplace,toWKTFunction function = ff.function(name,expr1,exprN);PropertyName property = ff.property(field);Literal v = ff.literal(value);Function min = ff.function("min", property, v);PropertyName property = ff.property(field);Literal search = ff.literal("search");Literal replace = ff.literal("replace");Literal all = ff.literal( true );Function replace = ff.function("strReplace", new Expression[]{property,search,replace,all});PropertyName property = ff.property(featureSource.schema.geometryDescriptor.localName);Function toWKT = ff.function("toWKT", property);查詢
/** * tableName 表名 * filter 過濾器 * List propNames 字段名列表 * * startIndex 起始位 * maxFeatures 最大條數 * sortField 排序字段名 * */ContentFeatureSource featureSource = (ContentFeatureSource) jdbcDataStore.getFeatureSource(tableName);//返回字段列List propertyNames = propNames.stream().map(ff::property).collect(Collectors.toList());Query query = new Query(tableName,filter,propertyNames)；int count = featureSource.getCount(query)；//計數// 分頁，倒序query.setStartIndex(startIndex);query.setMaxFeatures(maxFeatures);query.setSortBy(new SortByImpl(ff.property(sortField), SortOrder.DESCENDING));ContentFeatureCollection collection = featureSource.getFeatures(query);SimpleFeatureIterator iterator = collection.features();// SimpleFeatureIterator必須關閉，否則會造成內存泄漏iterator.close(); 新增
/*** tableName 圖層名* fieldName1 字段名* fieldValue1 字段值**/ContentFeatureSource featureSource = (ContentFeatureSource) jdbcDataStore.getFeatureSource(tableName);SimpleFeatureStore store = (SimpleFeatureStore)featureSource; // write access!SimpleFeatureBuilder featureBuilder = new SimpleFeatureBuilder(store.getSchema());featureBuilder.set(fieldName1,fieldValue1);featureBuilder.set(fieldNameN,fieldValueN);SimpleFeature feature = featureBuilder.buildFeature(null);ListFeatureCollection featureCollection = new ListFeatureCollection(store.getSchema(), List.of(feature));List addFeatures = store.addFeatures(featureCollection); 刪除
/**** typeName 圖層名* fliter 過濾條件**/ContentFeatureSource featureSource = (ContentFeatureSource) jdbcDataStore.getFeatureSource(tableName);SimpleFeatureStore store = (SimpleFeatureStore)featureSource; // write access!store.removeFeatures(filter);修改
/*** * typeName 圖層名* names 修改字段名數組* values 修改值數組* fliter 過濾條件* names和values順序保持一致*/ContentFeatureSource featureSource = (ContentFeatureSource) jdbcDataStore.getFeatureSource(tableName);SimpleFeatureStore store = (SimpleFeatureStore)featureSource; // write access!store.modifyFeature(names, values, filter)關鍵詞：
