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Difference between revisions of "XDI4j Tutorial 2"
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A typical application is to read an XDI graph from a file into memory, perform a few operations on it, and then store it again to file. | A typical application is to read an XDI graph from a file into memory, perform a few operations on it, and then store it again to file. | ||
| − | == Serialization | + | == Serialization == |
| − | + | '''Example Code:''' | |
<pre> | <pre> | ||
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package org.eclipse.higgins.xdi4j.tutorial; | package org.eclipse.higgins.xdi4j.tutorial; | ||
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* This example app shows how to output | * This example app shows how to output | ||
* a graph in different serialization formats. | * a graph in different serialization formats. | ||
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*/ | */ | ||
public class Tutorial2 { | public class Tutorial2 { | ||
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// let's create a simple graph | // let's create a simple graph | ||
| − | graph.createStatement(new XRI3Segment("= | + | graph.createStatement(new XRI3Segment("=alice"), new XRI3Segment("+name"), "Alice X."); |
| − | graph.createStatement(new XRI3Segment("= | + | graph.createStatement(new XRI3Segment("=alice"), new XRI3Segment("+friend"), new XRI3Segment("=bob")); |
// output the graph in X3 Simple and XDI/XML | // output the graph in X3 Simple and XDI/XML | ||
| Line 56: | Line 43: | ||
writer = XDIWriterRegistry.forFormat("XDI/XML"); | writer = XDIWriterRegistry.forFormat("XDI/XML"); | ||
| + | writer.write(graph, System.out, null); | ||
| + | |||
| + | graph.close(); | ||
| + | } | ||
| + | } | ||
| + | </pre> | ||
| + | |||
| + | == Deserialization == | ||
| + | |||
| + | '''Example Code:''' | ||
| + | |||
| + | <pre> | ||
| + | package org.eclipse.higgins.xdi4j.tutorial; | ||
| + | |||
| + | import java.io.File; | ||
| + | import java.io.FileInputStream; | ||
| + | |||
| + | import org.eclipse.higgins.xdi4j.Graph; | ||
| + | import org.eclipse.higgins.xdi4j.GraphFactory; | ||
| + | import org.eclipse.higgins.xdi4j.impl.memory.MemoryGraphFactory; | ||
| + | import org.eclipse.higgins.xdi4j.io.XDIReader; | ||
| + | import org.eclipse.higgins.xdi4j.io.XDIReaderRegistry; | ||
| + | import org.eclipse.higgins.xdi4j.io.XDIWriter; | ||
| + | import org.eclipse.higgins.xdi4j.io.XDIWriterRegistry; | ||
| + | |||
| + | /** | ||
| + | * This example app shows how to read a graph in one format | ||
| + | * and store it in another. | ||
| + | */ | ||
| + | public class Tutorial2A { | ||
| + | |||
| + | public static void main(String[] args) throws Exception { | ||
| + | |||
| + | GraphFactory factory = MemoryGraphFactory.getInstance(); | ||
| + | Graph graph = factory.openGraph(); | ||
| + | |||
| + | // read a graph from file | ||
| + | |||
| + | File file = new File("test.graph"); | ||
| + | XDIReader reader = XDIReaderRegistry.getAuto(); | ||
| + | |||
| + | reader.read(graph, new FileInputStream(file), null); | ||
| + | |||
| + | // output the graph in X3 Simple | ||
| + | |||
| + | XDIWriter writer; | ||
| + | |||
| + | writer = XDIWriterRegistry.forFormat("X3 Simple"); | ||
writer.write(graph, System.out, null); | writer.write(graph, System.out, null); | ||
Latest revision as of 08:57, 29 January 2010
{{#eclipseproject:technology.higgins|eclipse_custom_style.css}}
This tutorial explains how to serialize and deserialize an XDI graph in any of the XDI serialization formats.
A typical application is to read an XDI graph from a file into memory, perform a few operations on it, and then store it again to file.
Serialization
Example Code:
package org.eclipse.higgins.xdi4j.tutorial;
import org.eclipse.higgins.xdi4j.Graph;
import org.eclipse.higgins.xdi4j.GraphFactory;
import org.eclipse.higgins.xdi4j.impl.memory.MemoryGraphFactory;
import org.eclipse.higgins.xdi4j.io.XDIWriter;
import org.eclipse.higgins.xdi4j.io.XDIWriterRegistry;
import org.eclipse.higgins.xdi4j.xri3.impl.XRI3Segment;
/**
* This example app shows how to output
* a graph in different serialization formats.
*/
public class Tutorial2 {
public static void main(String[] args) throws Exception {
GraphFactory factory = MemoryGraphFactory.getInstance();
Graph graph = factory.openGraph();
// let's create a simple graph
graph.createStatement(new XRI3Segment("=alice"), new XRI3Segment("+name"), "Alice X.");
graph.createStatement(new XRI3Segment("=alice"), new XRI3Segment("+friend"), new XRI3Segment("=bob"));
// output the graph in X3 Simple and XDI/XML
XDIWriter writer;
writer = XDIWriterRegistry.forFormat("X3 Simple");
writer.write(graph, System.out, null);
writer = XDIWriterRegistry.forFormat("XDI/XML");
writer.write(graph, System.out, null);
graph.close();
}
}
Deserialization
Example Code:
package org.eclipse.higgins.xdi4j.tutorial;
import java.io.File;
import java.io.FileInputStream;
import org.eclipse.higgins.xdi4j.Graph;
import org.eclipse.higgins.xdi4j.GraphFactory;
import org.eclipse.higgins.xdi4j.impl.memory.MemoryGraphFactory;
import org.eclipse.higgins.xdi4j.io.XDIReader;
import org.eclipse.higgins.xdi4j.io.XDIReaderRegistry;
import org.eclipse.higgins.xdi4j.io.XDIWriter;
import org.eclipse.higgins.xdi4j.io.XDIWriterRegistry;
/**
* This example app shows how to read a graph in one format
* and store it in another.
*/
public class Tutorial2A {
public static void main(String[] args) throws Exception {
GraphFactory factory = MemoryGraphFactory.getInstance();
Graph graph = factory.openGraph();
// read a graph from file
File file = new File("test.graph");
XDIReader reader = XDIReaderRegistry.getAuto();
reader.read(graph, new FileInputStream(file), null);
// output the graph in X3 Simple
XDIWriter writer;
writer = XDIWriterRegistry.forFormat("X3 Simple");
writer.write(graph, System.out, null);
graph.close();
}
}