java - 执行.jar时将OJBDC添加到类路径

Question

我正在尝试开发一个连接到 Oracle 数据库并执行函数的 Java 应用程序。如果我在 Eclipse 中运行该应用程序，它可以工作，但是当我尝试在 Windows 命令提示符中运行 .jar 时，我收到“遇到错误:java.sql.SQLException:找不到合适的驱动程序”。

当我在命令行中执行时，我将传递 Eclipse 中 Maven 依赖项中显示的所有 .jar 文件的路径。

步骤

1. 执行“mvn clean install -U”

2. 使用“java -cp example-1.0-SNAPSHOT.jar;C:/Users/me/.m2/repository/junit/junit/4.11/junit-4.11-sources.jarC”从目标目录执行.jar :/Users/me/.m2/repository/org/hamcrest/hamcrest-core/1.3/hamcrest-core-1.3-sources.jar;C:/Users/me/.m2/repository/com/oracle/ojdbc/ojdbc10/19.3.0.0/ojdbc10-19.3.0.0-sources.jar;C:/Users/me/.m2/repository/com/oracle/ojdbc/ucp/19.3.0.0/ucp-19.3.0.0-sources.jar;C :/Users/me/.m2/repository/com/oracle/ojdbc/oraclepki/19.3.0.0/oraclepki-19.3.0.0-sources.jar;C:/Users/me/.m2/repository/com/oracle/ojdbc/osdt_cert/19.3.0.0/osdt_cert-19.3.0.0-sources.jar;C:/Users/me/.m2/repository/com/oracle/ojdbc/osdt_core/19.3.0.0/osdt_core-19.3.0.0-sources.jar ;C:/Users/me/.m2/repository/com/oracle/ojdbc/simplefan/19.3.0.0/simplefan-19.3.0.0-sources.jar;C:/Users/me/.m2/repository/com/oracle/ojdbc/ons/19.3.0.0/ons-19.3.0.0-sources.jar function.example.App"

3. 或者(如下所示)使用“java -cp example-1.0-SNAPSHOT.jar;C:/Users/me/.m2/repository/junit/junit/4.11/junit-4.11”从目标目录执行.jar。 jar;C:/Users/me/.m2/repository/org/hamcrest/hamcrest-core/1.3/hamcrest-core-1.3.jar;C:/Users/me/.m2/repository/com/oracle/ojdbc/ojdbc10/19.3.0.0/ojdbc10-19.3.0.0.jar;C:/Users/me/.m2/repository/com/oracle/ojdbc/ucp/19.3.0.0/ucp-19.3.0.0.jar;C:/Users/me/.m2/repository/com/oracle/ojdbc/oraclepki/19.3.0.0/oraclepki-19.3.0.0.jar;C:/Users/me/.m2/repository/com/oracle/ojdbc/osdt_cert/19.3。 0.0/osdt_cert-19.3.0.0.jar;C:/Users/me/.m2/repository/com/oracle/ojdbc/osdt_core/19.3.0.0/osdt_core-19.3.0.0.jar;C:/Users/me/. m2/repository/com/oracle/ojdbc/simplefan/19.3.0.0/simplefan-19.3.0.0.jar;C:/Users/me/.m2/repository/com/oracle/ojdbc/ons/19.3.0.0/ons- 19.3.0.0.jar函数.example.App”

申请

package function.example;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;

public class App {
    public static void main(String[] args) {
        String result = null;
        try {
            result = checkForPalindrome("racecar");
        } catch (SQLException e) {
            System.out.println("Error encountered: " + e);
            e.printStackTrace();
        }
        System.out.println(result);
    }

    public static Connection getConnection() {

        Properties prop = ReadPropertyFile();
        Connection conn = null;
        try {
            conn = DriverManager.getConnection(prop.getProperty("db.URL"), prop.getProperty("db.user"),
                    prop.getProperty("db.password"));
        } catch (SQLException e) {
            System.out.println("Error encountered: " + e);
            e.printStackTrace();
        }
        return conn;
    }

    public static String checkForPalindrome(String word) throws SQLException {
        String sql = "{? = call CHECKFORPALINDROME(?)}";
        try (Connection conn = getConnection(); java.sql.CallableStatement stmt = conn.prepareCall(sql);) {
            stmt.setString(2, word);
            stmt.registerOutParameter(1, java.sql.Types.VARCHAR);
            stmt.execute();
            String stmtResult = stmt.getString(1);
            return stmtResult;
        }
    }

    private static Properties ReadPropertyFile() {
        Properties prop = new Properties();
        try (InputStream input = new FileInputStream("c:\\config.properties")) {
            prop.load(input);
        } catch (FileNotFoundException e) {
            System.out.println("Error encountered: " + e);
            e.printStackTrace();
        } catch (IOException e) {
            System.out.println("Error encountered: " + e);
            e.printStackTrace();
        }
        return prop;
    }
}

POM

<project xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>function</groupId>
    <artifactId>example</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>jar</packaging>
    <name>ODB-function-example-pom</name>
    <url>http://maven.apache.org</url>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
            <scope>test</scope>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.oracle.ojdbc/ojdbc10 -->
        <dependency>
            <groupId>com.oracle.ojdbc</groupId>
            <artifactId>ojdbc10</artifactId>
            <version>19.3.0.0</version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.0</version>
                <configuration>
                    <release>8</release> 
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <configuration>
                    <archive>
                        <manifest>
                            <mainClass>function.example.App</mainClass>
                        </manifest>
                    </archive>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

修复

从我的 pom.xml 中删除了 ojdbc10 依赖项。从Oracle网站下载了ojdbc8(我似乎无法使用mvnrepository下载它)，在命令行中执行时将这些.jar文件手动添加到Eclipse和类路径中。

java -cp example-1.0-SNAPSHOT.jar;C:\Users\me\Desktop\ojdbc8-full* function.example.App

Answer 1

您的jar 似乎没有依赖项，因此您的oracles ojdbc 类未包含在最终的jar 中。你想要的是一个“ fat jar 子”。

实现方法 - 添加 Maven 插件，该插件将打包应用 jar 中的所有依赖项。这可以通过 maven-assemble-plugin 来实现:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-assembly-plugin</artifactId>
    <version>2.4.1</version>
    <configuration>
        <!-- get all project dependencies -->
        <descriptorRefs>
            <descriptorRef>jar-with-dependencies</descriptorRef>
        </descriptorRefs>
        <!-- MainClass in mainfest make a executable jar -->
        <archive>
            <manifest>
                <mainClass>function.example.App</mainClass>
            </manifest>
        </archive>
    </configuration>
    <executions>
        <execution>
            <id>make-assembly</id>
            <phase>package</phase> 
            <goals>
                <goal>single</goal>
            </goals>
        </execution>
    </executions>
</plugin>

因此，您运行 mvn package 后，您将拥有 jar-with-dependencies Artifact ，其中将包含所有依赖项。

更新

您的应用程序无法在运行时发现驱动程序类，因此您还必须手动加载它。它通常看起来像这样:

Class<?> clazz = Class.forName("oracle.jdbc.driver.OracleDriver");
Driver driver = (Driver) clazz.newInstance();
DriverManager.registerDriver(driver);