java - struts2 postgresql 找不到适合jdbc的驱动

Question

我正在尝试使用 Struts2 建立一个 jdbc 连接。但我收到一个异常(exception): java.sql.SQLException:找不到适合 jdbc 的驱动程序:postgresql://localhost:5432/postgres

这是我的代码:

package org.apache.struts.helloworld.action;

导入 com.opensymphony.xwork2.ActionSupport；

导入java.sql.DriverManager；导入 java.sql.ResultSet;

公共(public)类 HelloWorldAction 扩展 ActionSupport {

private static final long serialVersionUID = 1L;

/**
 * The model class that stores the message
 * to display in the view.
 */
//private MessageStore messageStore;
private String name;

/*
 * Creates the MessageStore model object and 
 * returns success.  The MessageStore model
 * object will be available to the view.
 * (non-Javadoc)
 * @see com.opensymphony.xwork2.ActionSupport#execute()
 */
public String execute() {
    String ret = ERROR;
    java.sql.Connection connection = null;

    try {

        Class.forName("org.postgresql:postgresql:9.4.1207.jre7");
        connection = DriverManager.getConnection("jdbc:postgresql://localhost:5432/postgres", "postgres", "*******");



        java.sql.Statement st = connection.createStatement();

        ResultSet rt = st.executeQuery("SELECT * FROM provider where id=1");


        while (rt.next()) {
            // System.out.println(rt.getString(2));

            name = rt.getString(2);
            ret = SUCCESS;

        }
        rt.close();
        st.close();
    } catch (ClassNotFoundException e) {
    System.out.println("Where is your MySQL JDBC Driver?");
    e.printStackTrace();

} catch (Exception e) {
        System.out.println(e.getStackTrace());
        return ERROR;
    }

    return ret;
}

我也有 maven 依赖

<dependency>
        <groupId>org.postgresql</groupId>
        <artifactId>postgresql</artifactId>
        <version>9.4.1207.jre7</version>
    </dependency>

附言我使用 Intellij Idea 14.1.4

有人知道原因吗？

Answer 1

PostgreSQL 的 JDBC 驱动是org.postgresql.Driver 所以

Class.forName("org.postgresql:postgresql:9.4.1207.jre7");

应该是

 Class.forName("org.postgresql.Driver");

虽然这是一个 JDBC 4 驱动程序，但您应该能够完全删除此语句...