Java Jena解析rdf内容错误

我实现了一个从rdf代码中解析一些信息的代码，但它引发了以下错误：

线程“main”com.hp.hpl.jena.query.QueryParseException中的异常：第1行第126列：未解析的前缀名称：foaf:name

导致此错误的问题是什么

这是我的代码：

import java.util.Iterator;

import com.hp.hpl.jena.query.Query;
import com.hp.hpl.jena.query.QueryExecution;
import com.hp.hpl.jena.query.QueryExecutionFactory;
import com.hp.hpl.jena.query.QueryFactory;
import com.hp.hpl.jena.query.QuerySolution;
import com.hp.hpl.jena.query.ResultSet;
import com.hp.hpl.jena.rdf.model.Literal;
import com.hp.hpl.jena.rdf.model.Model;
import com.hp.hpl.jena.util.FileManager;

public class Main {

    public static void main(String args[])
    {
        sparqlTest();
    }

    static void sparqlTest()
    {
        FileManager.get().addLocatorClassLoader(Main.class.getClassLoader());
        Model model = FileManager.get().loadModel("c:/Users/Laura/workspace/jena-app/src/data.rdf");

        String queryString = 
                "PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>" +
                "PREFIX foat: <http://xmlns.com/foaf/0.1/> " +
                "SELECT * WHERE { " +
                " ?person foaf:name ?x ." +
                "}";
        Query query = QueryFactory.create(queryString);
        QueryExecution qexec = QueryExecutionFactory.create(query, model);
        try {

            ResultSet results = qexec.execSelect();
            while (results.hasNext() ) {
                QuerySolution soln = results.nextSolution();
                Literal name = soln.getLiteral("x");
                System.out.println(name);
            }
        } finally {
            qexec.close();
        }

    }

}

---

您得到错误是因为您在下面的查询中将其指向了

foat

，而不是

foaf

"PREFIX foat: <http://xmlns.com/foaf/0.1/>"

“前缀foat：”

这应作如下更改：

"PREFIX foaf: <http://xmlns.com/foaf/0.1/>"

“前缀foaf：”

更新后的查询应如下所示：

String queryString = 
        "PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>" +
        "PREFIX foaf: <http://xmlns.com/foaf/0.1/>" +
        "SELECT * WHERE { " +
        " ?person foaf:name ?x ." +
        "}";

字符串查询字符串=
“前缀rdf：”+
“前缀foaf：”+
“选择*其中{”+
“人员foaf:姓名？x”+
"}";

可能是因为您在

前缀foat:

中指定了

foat

，而不是

foaf

！Daaannnggg。。。。谢谢，这个修好了！

"PREFIX foaf: <http://xmlns.com/foaf/0.1/>"

String queryString = 
        "PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>" +
        "PREFIX foaf: <http://xmlns.com/foaf/0.1/>" +
        "SELECT * WHERE { " +
        " ?person foaf:name ?x ." +
        "}";