为什么安卓应用无法与甲骨文数据库连接？

Question

我将ojdbc14.jar和oraclepki.jar添加到项目的libs文件夹中，下面是android项目的MainActivity.java:

package com.example.testoracle;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import android.app.Activity;
import android.database.SQLException;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        try {
            String userName = getDataFromOraDB();
            TextView tv = new TextView(this);
            tv.setText("Here is the name : "+userName);
            setContentView(tv);
            } catch (SQLException e) {
            Toast.makeText(this, "1st toast : "+e.getMessage(), Toast.LENGTH_LONG).show();
            } catch (ClassNotFoundException e) {
            Toast.makeText(this, "second toast : "+e.getMessage(), Toast.LENGTH_LONG).show();
            }
    }
    public String getDataFromOraDB() throws SQLException,
    ClassNotFoundException {
        String name = null;
        String jdbcURL = "jdbc:oracle:thin:@//localhost:1521:oracl";
        String user = "SYSTEM";
        String passwd = "root";
        // Load the Oracle JDBC driver
        try {
            Log.w("MyApp","Try");
            DriverManager.registerDriver(new oracle.jdbc.OracleDriver());
            Connection conn;
            ResultSet rs;
            Statement stmt;
            conn = DriverManager.getConnection(jdbcURL, user, passwd);
            stmt = conn.createStatement();
            Log.w("MyApp","Avant query");
            rs = stmt.executeQuery("select Name from table_people");
            Log.w("MyApp","Apres query");
            if (rs.next()) {
                name = rs.getString("Name");
            }
        } catch (java.sql.SQLException e) {
            // Auto-generated catch block
            System.out.println("the exception is : " + e.toString());
        }
        Toast.makeText(getApplicationContext(), "3rd toast : "+name, Toast.LENGTH_LONG).show();
        return name;
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }
}

舱单有INTERNET权限

<uses-permission android:name="android.permission.INTERNET" />

这是我在logcat

中得到的结果

06-01 15:16:34.142: W/MyApp(402): Try
06-01 15:16:34.373: I/dalvikvm(402): Failed resolving Loracle/jdbc/xa/OracleXAResource; interface 927 'Ljavax/transaction/xa/XAResource;'
06-01 15:16:34.373: W/dalvikvm(402): Link of class 'Loracle/jdbc/xa/OracleXAResource;' failed
06-01 15:16:34.373: W/dalvikvm(402): Unable to resolve superclass of Loracle/jdbc/xa/client/OracleXAResource; (1341)
06-01 15:16:34.373: W/dalvikvm(402): Link of class 'Loracle/jdbc/xa/client/OracleXAResource;' failed
06-01 15:16:34.373: W/dalvikvm(402): Unable to resolve superclass of Loracle/jdbc/driver/T4CXAResource; (1348)
06-01 15:16:34.373: W/dalvikvm(402): Link of class 'Loracle/jdbc/driver/T4CXAResource;' failed
06-01 15:16:34.373: W/dalvikvm(402): VFY: unable to find class referenced in signature (Loracle/jdbc/driver/T4CXAResource;)
06-01 15:16:34.373: I/dalvikvm(402): Failed resolving Loracle/jdbc/xa/OracleXAResource; interface 927 'Ljavax/transaction/xa/XAResource;'
06-01 15:16:34.383: W/dalvikvm(402): Link of class 'Loracle/jdbc/xa/OracleXAResource;' failed
06-01 15:16:34.383: W/dalvikvm(402): Unable to resolve superclass of Loracle/jdbc/xa/client/OracleXAResource; (1341)
06-01 15:16:34.383: W/dalvikvm(402): Link of class 'Loracle/jdbc/xa/client/OracleXAResource;' failed
06-01 15:16:34.383: W/dalvikvm(402): Unable to resolve superclass of Loracle/jdbc/driver/T4CXAResource; (1348)
06-01 15:16:34.383: W/dalvikvm(402): Link of class 'Loracle/jdbc/driver/T4CXAResource;' failed
06-01 15:16:34.383: I/dalvikvm(402): Could not find method oracle.jdbc.driver.T4CXAResource.setPasswordInternal, referenced from method oracle.jdbc.driver.T4CConnection.getPasswordInternal
06-01 15:16:34.383: W/dalvikvm(402): VFY: unable to resolve virtual method 10574: Loracle/jdbc/driver/T4CXAResource;.setPasswordInternal (Ljava/lang/String;)V
06-01 15:16:34.533: I/dalvikvm(402): Failed resolving Loracle/jdbc/pool/OracleDataSource; interface 850 'Ljavax/naming/Referenceable;'
06-01 15:16:34.533: W/dalvikvm(402): Link of class 'Loracle/jdbc/pool/OracleDataSource;' failed
06-01 15:16:34.533: I/dalvikvm(402): Could not find method oracle.jdbc.pool.OracleDataSource.filterConnectionProperties, referenced from method oracle.jdbc.driver.PhysicalConnection.getProperties
06-01 15:16:34.533: W/dalvikvm(402): VFY: unable to resolve static method 11805: Loracle/jdbc/pool/OracleDataSource;.filterConnectionProperties (Ljava/util/Properties;)Ljava/util/Properties;
06-01 15:16:34.543: W/dalvikvm(402): VFY: unable to find class referenced in signature (Ljavax/transaction/xa/XAResource;)
06-01 15:16:35.192: I/System.out(402): the exception is : java.sql.SQLException: Io exception: The Network Adapter could not establish the connection

那么有没有办法避免"网络适配器无法建立连接"呢?

Answer 1

这可能不是您想听到的，但是....

虽然您可以通过使用正确的数据库服务器地址并摆弄一堆其他位来实现此工作，但您真的不应该这样做。

Oracle是服务器端技术，而Android显然是客户端技术。大多数理智的人在很多年前就停止使用这种客户机-服务器数据库访问方式了，原因很充分……到现在它几乎成了一个怀旧的笑话。

IMHO，你应该构建一个服务器应用程序，用你选择的语言，呈现一个基于http的API (XML, JSON等)到你的Android应用程序。

然后，要么直接从Android应用程序中使用API，要么使用API来保持Android本地sqlite数据库与Oracle数据库的某些子集同步。

在你最喜欢的网络搜索引擎上有很多这样的例子。

Answer 2

1。-检查Oracle数据库是否正常运行

2。—如果是，请检查连接字符串是否正确，并根据数据库信息更改连接字符串。A)访问本地主机:https://localhost:1158/emb)登录用户名密码连接为-->正常c)在"常规"下面点击LISTENER_localhost查看端口号

Net Address (ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1522)) Connect to port 1522 

3。-检查是否有防火墙

也因为android会做一个网络调用，你不应该在主线程中这样做，使用线程或AsyncTask来连接。