Question

在tutorial about Vaadin 7 and SQLContainer之后我遇到了以下问题。我在Netbeans 8.0.2中进行编码，并希望在早期开发阶段使用嵌入式JavaDB / Derby数据库而不是JDBC。我正在尝试在我的Vaadin应用程序中对数据表进行数据绑定以显示数据。在init(VaadinRequest vaadinRequest)内，我调用了database()方法。

import com.vaadin.data.util.sqlcontainer.SQLContainer;
import com.vaadin.data.util.sqlcontainer.connection.JDBCConnectionPool;
import com.vaadin.data.util.sqlcontainer.connection.SimpleJDBCConnectionPool;
import com.vaadin.data.util.sqlcontainer.query.TableQuery;

private void database() {
    System.out.println("database()");
    JDBCConnectionPool pool = null;
    try {
        pool = new SimpleJDBCConnectionPool("org.apache.derby.jdbc.ClientDriver", 
                "jdbc:derby://localhost:1527/gr", "a", "a", 2, 5);
        TableQuery tq = new TableQuery("GROCERY", pool);
        tq.setVersionColumn("OPTLOCK");
        SQLContainer container = new SQLContainer(tq);  // <-- raises exception
        //container.setAutoCommit(true);
        Item i = container.addItem(1);
        Object props = i.getItemPropertyIds();
    } catch (SQLException ex) {
        Logger.getLogger(MyUI.class.getName()).log(Level.SEVERE, null, ex);
    }
}

而不是数据，我得到这个例外。我做错了什么或错过了什么？

java.sql.SQLSyntaxErrorException: Syntax error: Encountered "LIMIT" at line 1, column 41.
at org.apache.derby.client.am.SQLExceptionFactory40.getSQLException(Unknown Source)
at org.apache.derby.client.am.SqlException.getSQLException(Unknown Source)
at org.apache.derby.client.am.Connection.prepareStatement(Unknown Source)
at com.vaadin.data.util.sqlcontainer.query.TableQuery.executeQuery(TableQuery.java:526)
at com.vaadin.data.util.sqlcontainer.query.TableQuery.getResults(TableQuery.java:252)
at com.vaadin.data.util.sqlcontainer.SQLContainer.getPropertyIds(SQLContainer.java:1200)
at com.vaadin.data.util.sqlcontainer.SQLContainer.<init>(SQLContainer.java:134)
at org.darugna.MyUI.database(MyUI.java:294)
at org.darugna.MyUI.init(MyUI.java:194)
at com.vaadin.ui.UI.doInit(UI.java:675)
at com.vaadin.server.communication.UIInitHandler.getBrowserDetailsUI(UIInitHandler.java:214)
at com.vaadin.server.communication.UIInitHandler.synchronizedHandleRequest(UIInitHandler.java:74)
at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:41)
at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1408)
at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:351)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:344)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
at org.glassfish.tyrus.servlet.TyrusServletFilter.doFilter(TyrusServletFilter.java:295)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:316)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:415)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:282)
at com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:459)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:167)
at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:201)
at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:175)
at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:235)
at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:284)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:201)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:133)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:112)
at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:561)
at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:112)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:117)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:56)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:137)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:565)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:545)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.derby.client.am.SqlException: Syntax error: Encountered "LIMIT" at line 1, column 41.
at org.apache.derby.client.am.Statement.completeSqlca(Unknown Source)
at org.apache.derby.client.net.NetStatementReply.parsePrepareError(Unknown Source)
at org.apache.derby.client.net.NetStatementReply.parsePRPSQLSTTreply(Unknown Source)
at org.apache.derby.client.net.NetStatementReply.readPrepareDescribeOutput(Unknown Source)
at org.apache.derby.client.net.StatementReply.readPrepareDescribeOutput(Unknown Source)
at org.apache.derby.client.net.NetStatement.readPrepareDescribeOutput_(Unknown Source)
at org.apache.derby.client.am.Statement.readPrepareDescribeOutput(Unknown Source)
at org.apache.derby.client.am.PreparedStatement.readPrepareDescribeInputOutput(Unknown Source)
at org.apache.derby.client.am.PreparedStatement.flowPrepareDescribeInputOutput(Unknown Source)
at org.apache.derby.client.am.PreparedStatement.prepare(Unknown Source)
at org.apache.derby.client.am.Connection.prepareStatementX(Unknown Source)
... 47 more

这是我的表格架构

CREATE TABLE grocery (
    id INTEGER PRIMARY KEY,
    OPTLOCK INTEGER,
    name TEXT,
    category TEXT,
    price INTEGER
);

Answer 1

问题在于Derby 不支持支持SQL LIMIT。

必须提供自己的SQL生成器，以其他方式创建查询。

我在Janko Dimitroff that I found in Vaadin forums发布解决方案。

import com.vaadin.data.util.sqlcontainer.query.generator.DefaultSQLGenerator;

/**  
 * @author Janko Dimitroff
 */
@SuppressWarnings("serial")
public class DerbySQLGenerator extends DefaultSQLGenerator {

    public DerbySQLGenerator() {
    }

    /** Construct a DerbySQLGenerator with the specified identifiers for start and end of quoted strings. The identifiers
     * may be different depending on the database engine and it's settings.
     * 
     * @param quoteStart the identifier (character) denoting the start of a quoted string
     * @param quoteEnd the identifier (character) denoting the end of a quoted string */
    public DerbySQLGenerator(String quoteStart, String quoteEnd) {
        super(quoteStart, quoteEnd);
    }

    /** Generates the LIMIT and OFFSET clause.
     * 
     * @param sb StringBuffer to which the clause is appended.
     * @param offset Value for offset.
     * @param pagelength Value for pagelength.
     * @return StringBuffer with LIMIT and OFFSET clause added. */
    protected StringBuffer generateLimits(StringBuffer sb, int offset, int pagelength) {
        sb.append(" OFFSET ").append(offset).append(" ROWS").append(" FETCH NEXT ").append(pagelength).append(" ROWS ONLY");
        return sb;
    }
}

使用JavaDB / Derby的Vaadin SQLSyntaxErrorException：遇到＆＃34; LIMIT＆＃34;在第1栏第41栏

1 个答案: