我想使用H2数据库在我的Gluon Mobile应用程序上存储数据库。我尝试过JDBC，它在桌面版本上运行良好。但是我在Android上失败（org.h2.jdbc.JdbcSQLException：创建文件时出错）。
我拥有如下网址的更改连接，但没有运气 http://www.h2database.com/html/tutorial.html#android
已编辑以添加gradle
我的代码
try {
Connection connection=null;
lbError.setText("");
lbError.setVisible(false);
System.out.println("Label="+ label.getText());
//step1 load the driver class
Class.forName(DB_DRIVER).newInstance();
//step2 create the connection object
if(Platform.isDesktop())
connection=DriverManager.getConnection(DB_CONNECTION,DB_USER,DB_PASSWORD);
if(Platform.isAndroid())
connection = DriverManager.getConnection(DB_CONNECTION_ANDROID,DB_USER,DB_PASSWORD);
System.out.print("DATABASE Create");
//step3 create the statement object
Statement statement = connection.createStatement();
String sql="DROP TABLE IF EXISTS contact;\n" +
"CREATE TABLE contact(\n" +
" Id INT NOT NULL AUTO_INCREMENT,\n" +
" Name VARCHAR(255) NOT NULL,\n" +
" Email VARCHAR(255) NOT NULL UNIQUE,\n" +
" PRIMARY KEY (ID)\n" +
");";
System.out.println("SQL="+"\n"+sql);
//step4 execute query
statement.executeUpdate(sql);
System.out.println("Table Created");
} catch (Exception e) {
System.out.println("Error Line is here");
lbError.setText(e.toString());
lbError.setVisible(true);
e.printStackTrace();
}
堆栈跟踪：
07-10 10:30:38.770 30397 30435 W System.err: org.h2.jdbc.JdbcSQLException: Error while creating file "/data/data/com.khmerdev.views" [90062-196]
07-10 10:30:38.771 30397 30435 W System.err: at org.h2.store.fs.FilePathDisk.createDirectory(FilePathDisk.java:274)
07-10 10:30:38.772 30397 30435 W System.err: at org.h2.store.fs.FileUtils.createDirectory(FileUtils.java:42)
07-10 10:30:38.772 30397 30435 W System.err: at org.h2.store.fs.FileUtils.createDirectories(FileUtils.java:309)
07-10 10:30:38.772 30397 30435 W System.err: at org.h2.store.fs.FileUtils.createDirectories(FileUtils.java:308)
07-10 10:30:38.772 30397 30435 W System.err: at org.h2.mvstore.db.MVTableEngine.init(MVTableEngine.java:74)
07-10 10:30:38.772 30397 30435 W System.err: at org.h2.engine.Database.getPageStore(Database.java:2476)
07-10 10:30:38.772 30397 30435 W System.err: at org.h2.engine.Database.open(Database.java:697)
07-10 10:30:38.772 30397 30435 W System.err: at org.h2.engine.Database.openDatabase(Database.java:276)
07-10 10:30:38.772 30397 30435 W System.err: at org.h2.engine.Database.<init>(Database.java:270)
07-10 10:30:38.772 30397 30435 W System.err: at org.h2.engine.Engine.openSession(Engine.java:64)
07-10 10:30:38.773 30397 30435 W System.err: at org.h2.engine.Engine.openSession(Engine.java:176)
07-10 10:30:38.773 30397 30435 W System.err: at org.h2.engine.Engine.createSessionAndValidate(Engine.java:154)
07-10 10:30:38.773 30397 30435 W System.err: at org.h2.engine.Engine.createSession(Engine.java:137)
07-10 10:30:38.773 30397 30435 W System.err: at org.h2.engine.Engine.createSession(Engine.java:27)
07-10 10:30:38.773 30397 30435 W System.err: at org.h2.engine.SessionRemote.connectEmbeddedOrServer(SessionRemote.java:354)
07-10 10:30:38.773 30397 30435 W System.err: at org.h2.jdbc.JdbcConnection.<init>(JdbcConnection.java:116)
07-10 10:30:38.773 30397 30435 W System.err: at org.h2.jdbc.JdbcConnection.<init>(JdbcConnection.java:100)
07-10 10:30:38.773 30397 30435 W System.err: at org.h2.Driver.connect(Driver.java:69)
07-10 10:30:38.773 30397 30435 W System.err: at java.sql.DriverManager.getConnection(DriverManager.java:569)
07-10 10:30:38.773 30397 30435 W System.err: at java.sql.DriverManager.getConnection(DriverManager.java:219)
07-10 10:30:38.773 30397 30435 W System.err: at com.khmerdev.views.ContactPresenter.initDB(ContactPresenter.java:75)
07-10 10:30:38.773 30397 30435 W System.err: at com.khmerdev.views.ContactPresenter.initialize(ContactPresenter.java:53)
07-10 10:30:38.774 30397 30435 W System.err: at java.lang.reflect.Method.invoke(Native Method)
07-10 10:30:38.774 30397 30435 W System.err: at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
07-10 10:30:38.774 30397 30435 W System.err: at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:277)
07-10 10:30:38.774 30397 30435 W System.err: at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2566)
07-10 10:30:38.774 30397 30435 W System.err: at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2441)
07-10 10:30:38.774 30397 30435 W System.err: at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3214)
07-10 10:30:38.774 30397 30435 W System.err: at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3175)
07-10 10:30:38.774 30397 30435 W System.err: at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3148)
07-10 10:30:38.774 30397 30435 W System.err: at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3124)
07-10 10:30:38.774 30397 30435 W System.err: at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3104)
07-10 10:30:38.774 30397 30435 W System.err: at javafx.fxml.FXMLLoader.load(FXMLLoader.java:3097)
07-10 10:30:38.774 30397 30435 W System.err: at com.khmerdev.views.ContactView.getView(ContactView.java:11)
07-10 10:30:38.774 30397 30435 W System.err: at com.khmerdev.GluonApplication.lambda$init$0(GluonApplication.java:19)
07-10 10:30:38.775 30397 30435 W System.err: at com.khmerdev.GluonApplication$$Lambda$1.get(GluonApplication.java)
07-10 10:30:38.775 30397 30435 W System.err: at com.gluonhq.impl.charm.a.a.a.a(SourceFile:1032)
07-10 10:30:38.775 30397 30435 W System.err: at com.gluonhq.charm.glisten.application.MobileApplication.a(SourceFile:721)
07-10 10:30:38.775 30397 30435 W System.err: at com.gluonhq.charm.glisten.application.MobileApplication.switchView(SourceFile:475)
07-10 10:30:38.775 30397 30435 W System.err: at com.gluonhq.charm.glisten.application.MobileApplication.switchView(SourceFile:450)
07-10 10:30:38.775 30397 30435 W System.err: at com.gluonhq.charm.glisten.application.MobileApplication.a(SourceFile:266)
07-10 10:30:38.775 30397 30435 W System.err: at com.gluonhq.charm.glisten.application.MobileApplication.start(SourceFile:232)
07-10 10:30:38.775 30397 30435 W System.err: at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$145(LauncherImpl.java:863)
07-10 10:30:38.775 30397 30435 W System.err: at com.sun.javafx.application.LauncherImpl.access$lambda$8(LauncherImpl.java)
07-10 10:30:38.775 30397 30435 W System.err: at com.sun.javafx.application.LauncherImpl$$Lambda$9.run(Unknown Source)
07-10 10:30:38.775 30397 30435 W System.err: at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$158(PlatformImpl.java:326)
07-10 10:30:38.775 30397 30435 W System.err: at com.sun.javafx.application.PlatformImpl.access$lambda$6(PlatformImpl.java)
07-10 10:30:38.775 30397 30435 W System.err: at com.sun.javafx.application.PlatformImpl$$Lambda$7.run(Unknown Source)
07-10 10:30:38.775 30397 30435 W System.err: at com.sun.javafx.application.PlatformImpl.lambda$null$156(PlatformImpl.java:295)
07-10 10:30:38.776 30397 30435 W System.err: at com.sun.javafx.application.PlatformImpl.access$lambda$18(PlatformImpl.java)
07-10 10:30:38.776 30397 30435 W System.err: at com.sun.javafx.application.PlatformImpl$$Lambda$19.run(Unknown Source)
07-10 10:30:38.777 30397 30435 W System.err: at java.security.AccessController.doPrivileged(AccessController.java:57)
07-10 10:30:38.777 30397 30435 W System.err: at com.sun.javafx.application.PlatformImpl.lambda$runLater$157(PlatformImpl.java:294)
07-10 10:30:38.777 30397 30435 W System.err: at com.sun.javafx.application.PlatformImpl.access$lambda$5(PlatformImpl.java)
07-10 10:30:38.778 30397 30435 W System.err: at com.sun.javafx.application.PlatformImpl$$Lambda$6.run(Unknown Source)
07-10 10:30:38.778 30397 30435 W System.err: at com.sun.glass.ui.monocle.RunnableProcessor.runLoop(RunnableProcessor.java:93)
07-10 10:30:38.778 30397 30435 W System.err: at com.sun.glass.ui.monocle.RunnableProcessor.run(RunnableProcessor.java:52)
07-10 10:30:38.778 30397 30435 W System.err: at java.lang.Thread.run(Thread.java:762)
Build.gradle
buildscript {
repositories {
jcenter()
}
dependencies {
classpath 'org.javafxports:jfxmobile-plugin:1.3.12'
}
}
apply plugin: 'org.javafxports.jfxmobile'
repositories {
jcenter()
maven {
url 'http://nexus.gluonhq.com/nexus/content/repositories/releases'
}
}
mainClassName = 'com.khmerdev.GluonApplication'
dependencies {
compile 'com.gluonhq:charm:5.0.0'
compile files('libs/h2-1.4.196.jar')
}
jfxmobile {
downConfig {
version = '3.8.0'
// Do not edit the line below. Use Gluon Mobile Settings in your project context menu instead
plugins 'display', 'lifecycle', 'statusbar', 'storage'
}
android {
manifest = 'src/android/AndroidManifest.xml'
}
ios {
infoPList = file('src/ios/Default-Info.plist')
forceLinkClasses = [
'com.khmerdev.**.*',
'com.gluonhq.**.*',
'javax.annotations.**.*',
'javax.inject.**.*',
'javax.json.**.*',
'org.glassfish.json.**.*'
]
}
}
请帮助我。
答案 0 :(得分：0)
感谢JoséPereda给我一些想法，现在我找到了解决上述问题的方法。我们需要首先通过以下代码获取正确的私有存储：
File dir = Services.get(StorageService.class)
.map(s -> s.getPrivateStorage().get())
.orElseThrow(() -> new IOException("Error: PrivateStorage not available"));
以上代码的输出应为/data/user/0/com.khmerdev/files。然后，我们需要使用此目录与dbUrl串联。请参见以下示例：
String url = "jdbc:h2:/data/user/0/com.khmerdev/files" +
"/test" +
";FILE_LOCK=FS" +
";PAGE_SIZE=1024" +
";CACHE_SIZE=8192";
在上面的示例中，“ test”是示例数据库名称。因此，我们需要将此字符串url与JDBC一起使用，以进行数据库事务。