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public static void main(String[] args) throws Exception{ File f = new File("/opt/myImage.jpg"); String encodstring = encodeFileToBase64Binary(f); System.out.println(encodstring); } private static String encodeFileToBase64Binary(File file) throws Exception{ FileInputStream fileInputStreamReader = new FileInputStream(file); byte[] bytes = new byte[(int)file.length()]; fileInputStreamReader.read(bytes); return new String(Base64.encodeBase64(bytes), "UTF-8"); } |
Author: T Tak
Hey ! I'm Tak. I'm a software developer since 2008 and been programming since I was 17 years, started with pascal. I love programming, teaching and building stuff on web.
Geowave queries: Querying by polygon, Filtering on attributes of features using CQL queries, Ingesting polygons, and running polygon intersect queries
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import java.io.IOException; import java.util.ArrayList; import java.util.List; import org.apache.accumulo.core.client.AccumuloException; import org.apache.accumulo.core.client.AccumuloSecurityException; import org.apache.accumulo.core.client.Connector; import org.apache.accumulo.core.client.mock.MockInstance; import org.apache.accumulo.core.client.security.tokens.PasswordToken; import org.apache.log4j.Logger; import org.geotools.feature.AttributeTypeBuilder; import org.geotools.feature.simple.SimpleFeatureBuilder; import org.geotools.feature.simple.SimpleFeatureTypeBuilder; import org.geotools.filter.text.cql2.CQLException; import org.geotools.geometry.jts.JTSFactoryFinder; import org.opengis.feature.simple.SimpleFeature; import org.opengis.feature.simple.SimpleFeatureType; import com.vividsolutions.jts.geom.Coordinate; import com.vividsolutions.jts.geom.Geometry; import com.vividsolutions.jts.geom.Point; import com.vividsolutions.jts.io.ParseException; import com.vividsolutions.jts.io.WKTReader; import mil.nga.giat.geowave.adapter.vector.FeatureDataAdapter; import mil.nga.giat.geowave.adapter.vector.query.cql.CQLQuery; import mil.nga.giat.geowave.core.geotime.GeometryUtils; import mil.nga.giat.geowave.core.geotime.ingest.SpatialDimensionalityTypeProvider.SpatialIndexBuilder; import mil.nga.giat.geowave.core.geotime.store.query.SpatialQuery; import mil.nga.giat.geowave.core.index.ByteArrayId; import mil.nga.giat.geowave.core.store.CloseableIterator; import mil.nga.giat.geowave.core.store.DataStore; import mil.nga.giat.geowave.core.store.IndexWriter; import mil.nga.giat.geowave.core.store.adapter.AdapterStore; import mil.nga.giat.geowave.core.store.index.PrimaryIndex; import mil.nga.giat.geowave.core.store.memory.DataStoreUtils; import mil.nga.giat.geowave.core.store.query.QueryOptions; import mil.nga.giat.geowave.datastore.accumulo.AccumuloDataStore; import mil.nga.giat.geowave.datastore.accumulo.BasicAccumuloOperations; import mil.nga.giat.geowave.datastore.accumulo.metadata.AccumuloAdapterStore; /** * This class is intended to provide a few examples on running Geowave queries * of different types: 1- Querying by polygon a set of points. 2- Filtering on * attributes of features using CQL queries 3- Ingesting polygons, and running * polygon intersect queries. You can check all points, geometries and query * accuracy in a more visual manner @ http://geojson.io/ */ public class SpatialQueryExample { private static Logger log = Logger.getLogger(SpatialQueryExample.class); // We'll use GeoWave's VectorDataStore, which allows to run CQL rich queries private static DataStore dataStore; // We need the AccumuloAdapterStore, which keeps a registry of adapter-ids, // used to be able to query specific "tables" or "types" of features. private static AdapterStore adapterStore; public static void main( String[] args ) throws AccumuloSecurityException, AccumuloException, ParseException, CQLException, IOException { SpatialQueryExample example = new SpatialQueryExample(); log.info("Setting up datastores"); example.setupDataStores(); log.info("Running point query examples"); example.runPointExamples(); log.info("Running polygon query examples"); example.runPolygonExamples(); } private void setupDataStores() throws AccumuloSecurityException, AccumuloException { // Initialize VectorDataStore and AccumuloAdapterStore MockInstance instance = new MockInstance(); // For the MockInstance we can user "user" - "password" as our // connection tokens Connector connector = instance.getConnector( "user", new PasswordToken( "password")); BasicAccumuloOperations operations = new BasicAccumuloOperations( connector); dataStore = new AccumuloDataStore( operations); adapterStore = new AccumuloAdapterStore( operations); } /** * We'll run our point related operations. The data ingested and queried is * single point based, meaning the index constructed will be based on a * point. */ private void runPointExamples() throws ParseException, CQLException, IOException { ingestPointData(); pointQueryCase1(); pointQueryCase2(); pointQueryCase3(); pointQueryCase4(); } private void ingestPointData() { log.info("Ingesting point data"); ingestPointBasicFeature(); ingestPointComplexFeature(); log.info("Point data ingested"); } private void ingest( FeatureDataAdapter adapter, PrimaryIndex index, List features ) { try (IndexWriter indexWriter = dataStore.createWriter( adapter, index)) { for (SimpleFeature sf : features) { // indexWriter.write(sf); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } private void ingestPointBasicFeature() { // First, we'll build our first kind of SimpleFeature, which we'll call // "basic-feature" // We need the type builder to build the feature type SimpleFeatureTypeBuilder sftBuilder = new SimpleFeatureTypeBuilder(); // AttributeTypeBuilder for the attributes of the SimpleFeature AttributeTypeBuilder attrBuilder = new AttributeTypeBuilder(); // Here we're setting the SimpleFeature name. Later on, we'll be able to // query GW just by this particular feature. sftBuilder.setName("basic-feature"); // Add the attributes to the feature // Add the geometry attribute, which is mandatory for GeoWave to be able // to construct an index out of the SimpleFeature sftBuilder.add(attrBuilder.binding( Point.class).nillable( false).buildDescriptor( "geometry")); // Add another attribute just to be able to filter by it in CQL sftBuilder.add(attrBuilder.binding( String.class).nillable( false).buildDescriptor( "filter")); // Create the SimpleFeatureType SimpleFeatureType sfType = sftBuilder.buildFeatureType(); // We need the adapter for all our operations with GeoWave FeatureDataAdapter sfAdapter = new FeatureDataAdapter( sfType); // Now we build the actual features. We'll create two points. // First point SimpleFeatureBuilder sfBuilder = new SimpleFeatureBuilder( sfType); sfBuilder.set( "geometry", GeometryUtils.GEOMETRY_FACTORY.createPoint(new Coordinate( -80.211181640625, 25.848101000701597))); sfBuilder.set( "filter", "Basic-Stadium"); // When calling buildFeature, we need to pass an unique id for that // feature, or it will be overwritten. SimpleFeature basicPoint1 = sfBuilder.buildFeature("1"); // Construct the second feature. sfBuilder.set( "geometry", GeometryUtils.GEOMETRY_FACTORY.createPoint(new Coordinate( -80.191360, 25.777804))); sfBuilder.set( "filter", "Basic-College"); SimpleFeature basicPoint2 = sfBuilder.buildFeature("2"); ArrayList features = new ArrayList(); features.add(basicPoint1); features.add(basicPoint2); // Ingest the data. For that purpose, we need the feature adapter, // the index type (the default spatial index is used here), // and an iterator of SimpleFeature ingest( sfAdapter, new SpatialIndexBuilder().createIndex(), features); } /** * We're going to ingest a more complete simple feature. */ private void ingestPointComplexFeature() { // First, we'll build our second kind of SimpleFeature, which we'll call // "complex-feature" // We need the type builder to build the feature type SimpleFeatureTypeBuilder sftBuilder = new SimpleFeatureTypeBuilder(); // AttributeTypeBuilder for the attributes of the SimpleFeature AttributeTypeBuilder attrBuilder = new AttributeTypeBuilder(); // Here we're setting the SimpleFeature name. Later on, we'll be able to // query GW just by this particular feature. sftBuilder.setName("complex-feature"); // Add the attributes to the feature // Add the geometry attribute, which is mandatory for GeoWave to be able // to construct an index out of the SimpleFeature sftBuilder.add(attrBuilder.binding( Point.class).nillable( false).buildDescriptor( "geometry")); // Add another attribute just to be able to filter by it in CQL sftBuilder.add(attrBuilder.binding( String.class).nillable( false).buildDescriptor( "filter")); // Add more attributes to use with CQL filtering later on. sftBuilder.add(attrBuilder.binding( Double.class).nillable( false).buildDescriptor( "latitude")); sftBuilder.add(attrBuilder.binding( Double.class).nillable( false).buildDescriptor( "longitude")); // Create the SimpleFeatureType SimpleFeatureType sfType = sftBuilder.buildFeatureType(); // We need the adapter for all our operations with GeoWave FeatureDataAdapter sfAdapter = new FeatureDataAdapter( sfType); // Now we build the actual features. We'll create two more points. // First point SimpleFeatureBuilder sfBuilder = new SimpleFeatureBuilder( sfType); sfBuilder.set( "geometry", GeometryUtils.GEOMETRY_FACTORY.createPoint(new Coordinate( -80.193388, 25.780538))); sfBuilder.set( "filter", "Complex-Station"); sfBuilder.set( "latitude", 25.780538); sfBuilder.set( "longitude", -80.193388); // When calling buildFeature, we need to pass an unique id for that // feature, or it will be overwritten. SimpleFeature basicPoint1 = sfBuilder.buildFeature("1"); // Construct the second feature. sfBuilder.set( "geometry", GeometryUtils.GEOMETRY_FACTORY.createPoint(new Coordinate( -118.26713562011719, 33.988349152677955))); sfBuilder.set( "filter", "Complex-LA"); sfBuilder.set( "latitude", 33.988349152677955); sfBuilder.set( "longitude", -118.26713562011719); SimpleFeature basicPoint2 = sfBuilder.buildFeature("2"); ArrayList features = new ArrayList(); features.add(basicPoint1); features.add(basicPoint2); // Ingest the data. For that purpose, we need the feature adapter, // the index type (the default spatial index is used here), // and an iterator of SimpleFeature ingest( sfAdapter, new SpatialIndexBuilder().createIndex(), features); /** * After ingest, a single point might look like this in Accumulo. */ // x1Fx11xCBxFCxB6xEFTx00xFFcomplex_feature4x00x00x00x0Ex00x00x00x01x00x00x00x00 // complex_feature:filter [] Complex-LA // x1Fx11xCBxFCxB6xEFTx00xFFcomplex_feature4x00x00x00x0Ex00x00x00x01x00x00x00x00 // complex_feature:geomx00x00 [] // x00x00x00x00x01xC0][email protected]@xFEx829x9BxE3xFC // x1Fx11xCBxFCxB6xEFTx00xFFcomplex_feature4x00x00x00x0Ex00x00x00x01x00x00x00x00 // complex_feature:latitude [] @@xFEx829x9BxE3xFC // x1Fx11xCBxFCxB6xEFTx00xFFcomplex_featurex00x00x00x0Ex00x00x00x01x00x00x00x00 // complex_feature:longitude [] xC0]x91x18xC0x00x00x } /** * This query will search all points using the world's Bounding Box */ private void pointQueryCase1() throws ParseException, IOException { log.info("Running Point Query Case 1"); // First, we need to obtain the adapter for the SimpleFeature we want to // query. // We'll query basic-feature in this example. // Obtain adapter for our "basic-feature" type ByteArrayId bfAdId = new ByteArrayId( "basic-feature"); FeatureDataAdapter bfAdapter = (FeatureDataAdapter) adapterStore.getAdapter(bfAdId); // Define the geometry to query. We'll find all points that fall inside // that geometry String queryPolygonDefinition = "POLYGON (( " + "-180 -90, " + "-180 90, " + "180 90, " + "180 -90, " + "-180 -90" + "))"; Geometry queryPolygon = new WKTReader( JTSFactoryFinder.getGeometryFactory()).read(queryPolygonDefinition); // Perform the query.Parameters are /** * 1- Adapter previously obtained from the feature name. 2- Default * spatial index. 3- A SpatialQuery, which takes the query geometry - * aka Bounding box 4- Filters. For this example, no filter is used. 5- * Limit. Same as standard SQL limit. 0 is no limits. 6- Accumulo * authorizations. For our mock instances, "root" works. In a real * Accumulo setting, whatever authorization is associated to the user in * question. */ final QueryOptions options = new QueryOptions( bfAdapter, new SpatialIndexBuilder().createIndex()); options.setAuthorizations(new String[] { "root" }); int count = 0; try (final CloseableIterator iterator = dataStore.query( options, new SpatialQuery( queryPolygon))) { while (iterator.hasNext()) { SimpleFeature sf = iterator.next(); log.info("Obtained SimpleFeature " + sf.getName().toString() + " - " + sf.getAttribute("filter")); count++; System.out.println("Query match: " + iterator.next().getID()); } log.info("Should have obtained 2 features. -> " + (count == 2)); } } /** * This query will use a specific Bounding Box, and will find only 1 point. */ private void pointQueryCase2() throws ParseException, IOException { log.info("Running Point Query Case 2"); // First, we need to obtain the adapter for the SimpleFeature we want to // query. // We'll query complex-feature in this example. // Obtain adapter for our "complex-feature" type ByteArrayId bfAdId = new ByteArrayId( "complex-feature"); FeatureDataAdapter bfAdapter = (FeatureDataAdapter) adapterStore.getAdapter(bfAdId); // Define the geometry to query. We'll find all points that fall inside // that geometry. String queryPolygonDefinition = "POLYGON (( " + "-118.50059509277344 33.75688594085081, " + "-118.50059509277344 34.1521587488017, " + "-117.80502319335938 34.1521587488017, " + "-117.80502319335938 33.75688594085081, " + "-118.50059509277344 33.75688594085081" + "))"; Geometry queryPolygon = new WKTReader( JTSFactoryFinder.getGeometryFactory()).read(queryPolygonDefinition); // Perform the query.Parameters are /** * 1- Adapter previously obtained from the feature name. 2- Default * spatial index. 3- A SpatialQuery, which takes the query geometry - * aka Bounding box 4- Filters. For this example, no filter is used. 5- * Limit. Same as standard SQL limit. 0 is no limits. 6- Accumulo * authorizations. For our mock instances, "root" works. In a real * Accumulo setting, whatever authorization is associated to the user in * question. */ final QueryOptions options = new QueryOptions( bfAdapter, new SpatialIndexBuilder().createIndex(), new String[] { "root" }); int count = 0; try (final CloseableIterator iterator = dataStore.query( options, new SpatialQuery( queryPolygon))) { while (iterator.hasNext()) { SimpleFeature sf = iterator.next(); log.info("Obtained SimpleFeature " + sf.getName().toString() + " - " + sf.getAttribute("filter")); count++; System.out.println("Query match: " + sf.getID()); } log.info("Should have obtained 1 feature. -> " + (count == 1)); } } /** * This query will use the world's Bounding Box together with a CQL filter. */ private void pointQueryCase3() throws ParseException, CQLException, IOException { log.info("Running Point Query Case 3"); // First, we need to obtain the adapter for the SimpleFeature we want to // query. // We'll query basic-feature in this example. // Obtain adapter for our "basic-feature" type ByteArrayId bfAdId = new ByteArrayId( "basic-feature"); FeatureDataAdapter bfAdapter = (FeatureDataAdapter) adapterStore.getAdapter(bfAdId); String CQLFilter = "filter = 'Basic-Stadium'"; // Perform the query.Parameters are /** * 1- Adapter previously obtained from the feature name. 2- Default * spatial index. 3- A SpatialQuery, which takes the query geometry - * aka Bounding box 4- Filters. For this example, we reduce all returned * points (2) by using a filter. 5- Limit. Same as standard SQL limit. 0 * is no limits. 6- Accumulo authorizations. For our mock instances, * "root" works. In a real Accumulo setting, whatever authorization is * associated to the user in question. */ final QueryOptions options = new QueryOptions( bfAdapter, new SpatialIndexBuilder().createIndex(), new String[] { "root" }); int count = 0; try (final CloseableIterator iterator = dataStore.query( options, new CQLQuery( CQLFilter, bfAdapter))) { // Our query would have found 2 points based only on the Bounding // Box, but using the // filter to match a particular attribute will reduce our result set // size to 1 while (iterator.hasNext()) { SimpleFeature sf = iterator.next(); log.info("Obtained SimpleFeature " + sf.getName().toString() + " - " + sf.getAttribute("filter")); count++; System.out.println("Query match: " + sf.getID()); } log.info("Should have obtained 1 feature. " + (count == 1)); } } /** * This query will use the world's Bounding Box together with a more complex * CQL filter. */ private void pointQueryCase4() throws ParseException, CQLException, IOException { log.info("Running Point Query Case 4"); // First, we need to obtain the adapter for the SimpleFeature we want to // query. // We'll query complex-feature in this example. // Obtain adapter for our "complex-feature" type ByteArrayId bfAdId = new ByteArrayId( "complex-feature"); FeatureDataAdapter bfAdapter = (FeatureDataAdapter) adapterStore.getAdapter(bfAdId); // This CQL query will yield a single point - Complex-LA String CQLFilter = "latitude > 25 AND longitude < -118"; // Perform the query.Parameters are /** * 1- Adapter previously obtained from the feature name. 2- Default * spatial index. 3- A SpatialQuery, which takes the query geometry - * aka Bounding box 4- Filters. For this example, we reduce all returned * points (2) by using a filter. 5- Limit. Same as standard SQL limit. 0 * is no limits. 6- Accumulo authorizations. For our mock instances, * "root" works. In a real Accumulo setting, whatever authorization is * associated to the user in question. */ final QueryOptions options = new QueryOptions( bfAdapter, new SpatialIndexBuilder().createIndex(), new String[] { "root" }); int count = 0; try (final CloseableIterator iterator = dataStore.query( options, new CQLQuery( CQLFilter, bfAdapter))) { // Our query would have found 2 points based only on the Bounding // Box, but using the // filter to match a particular attribute will reduce our result set // size to 1 while (iterator.hasNext()) { SimpleFeature sf = iterator.next(); log.info("Obtained SimpleFeature " + sf.getName().toString() + " - " + sf.getAttribute("filter")); count++; System.out.println("Query match: " + sf.getID()); } log.info("Should have obtained 1 feature. -> " + (count == 1)); } } /** * We'll run our polygon related operations. The data ingested and queried * is single polygon based, meaning the index constructed will be based on a * Geometry. */ private void runPolygonExamples() throws ParseException, IOException { ingestPolygonFeature(); polygonQueryCase1(); } private void ingestPolygonFeature() throws ParseException { log.info("Ingesting polygon data"); // First, we'll build our third kind of SimpleFeature, which we'll call // "polygon-feature" // We need the type builder to build the feature type SimpleFeatureTypeBuilder sftBuilder = new SimpleFeatureTypeBuilder(); // AttributeTypeBuilder for the attributes of the SimpleFeature AttributeTypeBuilder attrBuilder = new AttributeTypeBuilder(); // Here we're setting the SimpleFeature name. Later on, we'll be able to // query GW just by this particular feature. sftBuilder.setName("polygon-feature"); // Add the attributes to the feature // Add the geometry attribute, which is mandatory for GeoWave to be able // to construct an index out of the SimpleFeature // Will be any arbitrary geometry; in this case, a polygon. sftBuilder.add(attrBuilder.binding( Geometry.class).nillable( false).buildDescriptor( "geometry")); // Add another attribute just to be able to filter by it in CQL sftBuilder.add(attrBuilder.binding( String.class).nillable( false).buildDescriptor( "filter")); // Create the SimpleFeatureType SimpleFeatureType sfType = sftBuilder.buildFeatureType(); // We need the adapter for all our operations with GeoWave FeatureDataAdapter sfAdapter = new FeatureDataAdapter( sfType); // Now we build the actual features. We'll create one polygon. // First point SimpleFeatureBuilder sfBuilder = new SimpleFeatureBuilder( sfType); // For ease of use, we'll create the polygon geometry with WKT format. String polygonDefinition = "POLYGON (( " + "-80.3045654296875 25.852426562716428, " + "-80.123291015625 25.808545671771615, " + "-80.19195556640625 25.7244467526159, " + "-80.34233093261719 25.772068899816585, " + "-80.3045654296875 25.852426562716428" + "))"; Geometry geom = new WKTReader( JTSFactoryFinder.getGeometryFactory()).read(polygonDefinition); sfBuilder.set( "geometry", geom); sfBuilder.set( "filter", "Polygon"); // When calling buildFeature, we need to pass an unique id for that // feature, or it will be overwritten. SimpleFeature polygon = sfBuilder.buildFeature("1"); ArrayList features = new ArrayList(); features.add(polygon); // Ingest the data. For that purpose, we need the feature adapter, // the index type (the default spatial index is used here), // and an iterator of SimpleFeature ingest( sfAdapter, new SpatialIndexBuilder().createIndex(), features); log.info("Polygon data ingested"); } /** * This query will find a polygon/polygon intersection, returning one match. */ private void polygonQueryCase1() throws ParseException, IOException { log.info("Running Point Query Case 4"); // First, we need to obtain the adapter for the SimpleFeature we want to // query. // We'll query polygon-feature in this example. // Obtain adapter for our "polygon-feature" type ByteArrayId bfAdId = new ByteArrayId( "polygon-feature"); FeatureDataAdapter bfAdapter = (FeatureDataAdapter) adapterStore.getAdapter(bfAdId); // Define the geometry to query. We'll find all polygons that intersect // with this geometry. String queryPolygonDefinition = "POLYGON (( " + "-80.4037857055664 25.81596330265488, " + "-80.27915954589844 25.788144792391982, " + "-80.34370422363281 25.8814655232439, " + "-80.44567108154297 25.896291175546626, " + "-80.4037857055664 25.81596330265488" + "))"; Geometry queryPolygon = new WKTReader( JTSFactoryFinder.getGeometryFactory()).read(queryPolygonDefinition); // Perform the query.Parameters are /** * 1- Adapter previously obtained from the feature name. 2- Default * spatial index. 3- A SpatialQuery, which takes the query geometry - * aka Bounding box 4- Filters. For this example, we don't use filters * 5- Limit. Same as standard SQL limit. 0 is no limits. 6- Accumulo * authorizations. For our mock instances, "root" works. In a real * Accumulo setting, whatever authorization is associated to the user in * question. */ final QueryOptions options = new QueryOptions( bfAdapter, new SpatialIndexBuilder().createIndex(), new String[] { "root" }); int count = 0; try (final CloseableIterator iterator = dataStore.query( options, new SpatialQuery( queryPolygon))) { while (iterator.hasNext()) { SimpleFeature sf = iterator.next(); log.info("Obtained SimpleFeature " + sf.getName().toString() + " - " + sf.getAttribute("filter")); count++; System.out.println("Query match: " + sf.getID()); } log.info("Should have obtained 1 feature. -> " + (count == 1)); } } } |
Append string prefix if string doesn’t have the prefix
Here is the one liner that appends the string with a prefix if the string doesn’t have a prefix
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String newString = oldString.startsWith("someprefix") ? oldString : "someprefix" + oldString; |
Jsoup Maven and gradle dependecies
jsoup is a Java library for working with real-world HTML. It provides a very convenient API for extracting and manipulating data, using the best of DOM, CSS, and jquery-like methods. Maven If you use Maven to manage the dependencies in your Java project, you do not need to download; just place the following into your […]
ArrayList in java , add() method
Here is a real world example of using java.util.ArrayList add method.
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/* Soot - a J*va Optimization Framework * Copyright (C) 2003 Jennifer Lhotak * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ import java.util.ArrayList; import java.util.Iterator; import org.eclipse.jface.action.*; /** * Launches Soot with -f J for all classes in output dir of * selected project */ public class SootJimpleJavaProjectLauncher extends SootProjectLauncher { public void run(IAction action) { super.run(action); setCmd(); runSootDirectly(); runFinish(); } private void setCmd() { ArrayList commands = new ArrayList(); commands.add("--"+LaunchCommands.SOOT_CLASSPATH); Iterator it = getJavaProcessPath().iterator(); String cp = (String)it.next(); while (it.hasNext()){ cp = cp + getSootClasspath().getSeparator() + (String)it.next(); } cp = cp + getSootClasspath().getSeparator() + getClasspathAppend(); commands.add(cp); commands.add("--"+LaunchCommands.OUTPUT_DIR); commands.add(getOutputLocation()); getSootCommandList().addSingleOpt("--"+LaunchCommands.KEEP_LINE_NUMBER); getSootCommandList().addSingleOpt("--"+LaunchCommands.XML_ATTRIBUTES); Iterator it2 = getJavaProcessPath().iterator(); while (it2.hasNext()){ commands.add("--"+LaunchCommands.PROCESS_PATH); commands.add((String)it2.next()); } getSootCommandList().addDoubleOpt("--"+LaunchCommands.OUTPUT, LaunchCommands.JIMPLE_OUT); getSootCommandList().addDoubleOpt("--"+LaunchCommands.SRC_PREC,"java"); getSootCommandList().addSingleOpt(commands); } } |
Sort a list in java
Here is a nice example of sorting of a list
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package com.javagist.sort; import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; import java.util.List; /** * This program sorts a list of Strings in ascending and descending order. * * @author javagist * */ public class SortExample { private List<String> namesList = Arrays.asList("Kevin", "Brian" , "Steve", "Bill", "Obama"); public static void main(String[] args) { SortExample sortExample = new SortExample(); System.out.println("Before sorting:" + sortExample.namesList); sortExample.sortList(sortExample.namesList); System.out.println("List in ascending order:" + sortExample.namesList); sortExample.reverseSortList(sortExample.namesList); System.out.println("List in descending orde :" + sortExample.namesList); // sort a new list and don't modify the order of original list List<String> keepOriginalOrderList = Arrays.asList("Kevin", "Brian" , "Steve", "Bill", "Obama"); List<String> sortedList = sortExample.sortListWithoutModifyingOriginalList(keepOriginalOrderList); System.out.println("List has preserved order :" + keepOriginalOrderList); System.out.println("New sorted list :" + sortedList); } /** * This method makes it obvious that any object that extends comparable can be sorted. * @param list - list to be sorted */ private <E extends Comparable<E>> void sortList(List<E> list){ Collections.sort(list); } /** * This method makes it obvious that any object that extends comparable can be sorted. * @param list - list to be reverse sorted */ private <E extends Comparable<E>> void reverseSortList(List<E> list){ Collections.sort(list, Collections.reverseOrder()); } /** * This method preserves the original List ordering. And returns a new sorted list * @param list - list to be sorted but not modified */ private <E extends Comparable<E>> List<E> sortListWithoutModifyingOriginalList(List<E> list){ List<E> newList = new ArrayList<E>(list); Collections.sort(newList); return newList; } } |
References http://programtalk.com/java/sort-list-java/
How to forwarding X11 connections from a remote host using sshj in java
This example demonstrates how forwarding X11 connections from a remote host can be accomplished.
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import net.schmizz.sshj.SSHClient; import net.schmizz.sshj.common.StreamCopier; import net.schmizz.sshj.connection.channel.direct.Session; import net.schmizz.sshj.connection.channel.direct.Session.Command; import net.schmizz.sshj.connection.channel.forwarded.SocketForwardingConnectListener; import java.io.IOException; import java.net.InetSocketAddress; public class X11 { public static void main(String... args) throws IOException, InterruptedException { final SSHClient ssh = new SSHClient(); // Compression makes X11 more feasible over slower connections // ssh.useCompression(); ssh.loadKnownHosts(); // NOTE: Forwarding incoming X connections to localhost:6000 only works if X is started without the // "-nolisten tcp" option (this is usually not the default for good reason) ssh.registerX11Forwarder(new SocketForwardingConnectListener(new InetSocketAddress("localhost", 6000))); ssh.connect("localhost"); try { ssh.authPublickey(System.getProperty("user.name")); Session sess = ssh.startSession(); // It is recommendable to send a fake cookie, and in your ConnectListener when a connection comes in replace // it with the real one. But here simply one from `xauth list` is being used. sess.reqX11Forwarding("MIT-MAGIC-COOKIE-1", "b0956167c9ad8f34c8a2788878307dc9", 0); final Command cmd = sess.exec("/usr/X11/bin/xcalc"); new StreamCopier(cmd.getInputStream(), System.out).spawn("stdout"); new StreamCopier(cmd.getErrorStream(), System.err).spawn("stderr"); // Wait for session & X11 channel to get closed ssh.getConnection().join(); } finally { ssh.disconnect(); } } } |
Retrofit Crawler
A simple web crawler that uses a Retrofit service to turn URLs into webpages.
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/* * Copyright (C) 2016 Square, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.example.retrofit; import java.io.IOException; import java.lang.annotation.Annotation; import java.lang.reflect.Type; import java.util.ArrayList; import java.util.Collections; import java.util.LinkedHashSet; import java.util.List; import java.util.Set; import java.util.concurrent.ConcurrentHashMap; import java.util.concurrent.Executors; import java.util.concurrent.TimeUnit; import java.util.concurrent.atomic.AtomicInteger; import okhttp3.ConnectionPool; import okhttp3.Dispatcher; import okhttp3.HttpUrl; import okhttp3.OkHttpClient; import okhttp3.ResponseBody; import org.jsoup.Jsoup; import org.jsoup.nodes.Document; import org.jsoup.nodes.Element; import retrofit2.Call; import retrofit2.Callback; import retrofit2.Converter; import retrofit2.Response; import retrofit2.Retrofit; import retrofit2.http.GET; import retrofit2.http.Url; public final class Crawler { private final Set fetchedUrls = Collections.synchronizedSet( new LinkedHashSet()); private final ConcurrentHashMap hostnames = new ConcurrentHashMap<>(); private final PageService pageService; public Crawler(PageService pageService) { this.pageService = pageService; } public void crawlPage(HttpUrl url) { // Skip hosts that we've visited many times. AtomicInteger hostnameCount = new AtomicInteger(); AtomicInteger previous = hostnames.putIfAbsent(url.host(), hostnameCount); if (previous != null) hostnameCount = previous; if (hostnameCount.incrementAndGet() > 100) return; // Asynchronously visit URL. pageService.get(url).enqueue(new Callback() { @Override public void onResponse(Call call, Response response) { if (!response.isSuccessful()) { System.out.println(call.request().url() + ": failed: " + response.code()); return; } // Print this page's URL and title. Page page = response.body(); HttpUrl base = response.raw().request().url(); System.out.println(base + ": " + page.title); // Enqueue its links for visiting. for (String link : page.links) { HttpUrl linkUrl = base.resolve(link); if (linkUrl != null && !fetchedUrls.add(linkUrl)) { crawlPage(linkUrl); } } } @Override public void onFailure(Call call, Throwable t) { System.out.println(call.request().url() + ": failed: " + t); } }); } public static void main(String... args) throws Exception { Dispatcher dispatcher = new Dispatcher(Executors.newFixedThreadPool(20)); dispatcher.setMaxRequests(20); dispatcher.setMaxRequestsPerHost(1); OkHttpClient okHttpClient = new OkHttpClient.Builder() .dispatcher(dispatcher) .connectionPool(new ConnectionPool(100, 30, TimeUnit.SECONDS)) .build(); Retrofit retrofit = new Retrofit.Builder() .baseUrl(HttpUrl.parse("https://example.com/")) .addConverterFactory(PageAdapter.FACTORY) .client(okHttpClient) .build(); PageService pageService = retrofit.create(PageService.class); Crawler crawler = new Crawler(pageService); crawler.crawlPage(HttpUrl.parse(args[0])); } interface PageService { @GET Call get(@Url HttpUrl url); } static class Page { public final String title; public final List links; public Page(String title, List links) { this.title = title; this.links = links; } } static final class PageAdapter implements Converter { static final Converter.Factory FACTORY = new Converter.Factory() { @Override public Converter responseBodyConverter( Type type, Annotation[] annotations, Retrofit retrofit) { if (type == Page.class) return new PageAdapter(); return null; } }; @Override public Page convert(ResponseBody responseBody) throws IOException { Document document = Jsoup.parse(responseBody.string()); List links = new ArrayList<>(); for (Element element : document.select("a[href]")) { links.add(element.attr("href")); } return new Page(document.title(), Collections.unmodifiableList(links)); } } } |
Convert byte to Hexadecimal String and vice versa
Convert byte to Hexadecimal
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public static String bytesToHex(byte[] bytes) { final char[] hexArray = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' }; char[] hexChars = new char[bytes.length * 2]; int v; for (int j = 0; j < bytes.length; j++) { v = bytes[j] & 0xFF; hexChars[j * 2] = hexArray[v >>> 4]; hexChars[j * 2 + 1] = hexArray[v & 0x0F]; } return new String(hexChars); } |
Convert Hexadecimal to byte
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public static byte[] hexToBytes(String s) { int len = s.length(); byte[] data = new byte[len / 2]; for (int i = 0; i < len; i += 2) { data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4) + Character.digit(s.charAt(i + 1), 16)); } return data; } |
How to download and Upload a file through SFTP using java.
Here is a code example that shows how to download and upload a file through SFTP in java Download File
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import com.jcraft.jsch.Channel; import com.jcraft.jsch.ChannelSftp; import com.jcraft.jsch.JSch; import com.jcraft.jsch.JSchException; import com.jcraft.jsch.Session; import com.jcraft.jsch.SftpException; /** * * @author javagists.com * */ public class DownloadFileSFTP { public static void main(String[] args) throws Exception { JSch jsch = new JSch(); Session session = null; try { session = jsch.getSession("admin", "127.0.0.1", 22); session.setConfig("StrictHostKeyChecking", "no"); session.setPassword("pass"); session.connect(); Channel channel = session.openChannel("sftp"); channel.connect(); ChannelSftp sftpChannel = (ChannelSftp) channel; sftpChannel.get("/tmpremote/testDownload.txt", "/tmplocal/testDownload.txt"); sftpChannel.exit(); session.disconnect(); } catch (JSchException e) { e.printStackTrace(); } catch (SftpException e) { e.printStackTrace(); } } } |
Upload File
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import com.jcraft.jsch.Channel; import com.jcraft.jsch.ChannelSftp; import com.jcraft.jsch.JSch; import com.jcraft.jsch.JSchException; import com.jcraft.jsch.Session; import com.jcraft.jsch.SftpException; /** * * @author javagists.com * */ public class UploadFileSFTP { public static void main(String[] args) throws Exception { JSch jsch = new JSch(); Session session = null; try { session = jsch.getSession("admin", "127.0.0.1", 22); session.setConfig("StrictHostKeyChecking", "no"); session.setPassword("pass"); session.connect(); Channel channel = session.openChannel("sftp"); channel.connect(); ChannelSftp sftpChannel = (ChannelSftp) channel; sftpChannel.put("/tmplocal/testUpload.txt", "/tmpremote/testUpload.txt"); sftpChannel.exit(); session.disconnect(); } catch (JSchException e) { e.printStackTrace(); } catch (SftpException e) { e.printStackTrace(); } } } |
