我在使用带有 Java 的 sqlite 时遇到问题。我的应用程序在第一次启动时会在 jar 文件所在的文件夹中创建一个文件夹，并在该文件夹中放置我的 sqlite db；问题是，当我从 Netbeans 运行我的项目时，一切正常，没有任何问题，但是当我构建 jar 并尝试从中执行它时，应用程序会创建文件夹而不是内部的 db，并且程序会崩溃。为什么？这是我创建数据库及其文件夹的代码：
public Db()
{
if (!checker())
{
File f = new File("dbecprp");
f.mkdir();
try {
String url = "jdbc:sqlite:dbecprp/dbecprp.db";
Class.forName("org.sqlite.JDBC");
conn = (Connection)DriverManager.getConnection(url);
s = conn.createStatement();
s.executeUpdate("CREATE TABLE Utente (idUtente integer primary key autoincrement, nome varchar(45) not null, email varchar(45) not null, password varchar(15) not null);");
s.executeUpdate("CREATE TABLE Prodotto (idProdotto integer primary key autoincrement, tipologia varchar(3) not null, titolo varchar(45) not null, creatore varchar(45) not null, prezzo float not null, descrizione varchar(45), qta_magazzino int(3) not null);");
s.executeUpdate("CREATE TABLE Ordine (idOrdine integer primary key autoincrement, qta_prodotto int(3) not null, totale_ordine float not null, data_ordine long not null, nome_consegna varchar(45) not null, indirizzo_spedizione varchar(150) not null, idUtente int not null, idProdotto int not null, FOREIGN KEY (idUtente) REFERENCES Utente(idUtente), FOREIGN KEY (idProdotto) REFERENCES Prodotto(idProdotto));");
} catch (ClassNotFoundException | SQLException ex) {
JOptionPane.showMessageDialog(null, "Db creation failed. Program will terminate.");
System.exit(1);
}
filler();
}
}
public boolean checker()
{
File f = new File("dbecprp");
return f.isDirectory();
}
这是干净和构建的输出：
ant -f C:\\Users\\paolo2\\Documents\\NetBeansProjects\\Server clean jar
init:
deps-clean:
Updating property file: C:\Users\paolo2\Documents\NetBeansProjects\Server\build\built-clean.properties
Deleting directory C:\Users\paolo2\Documents\NetBeansProjects\Server\build
clean:
init:
deps-jar:
Created dir: C:\Users\paolo2\Documents\NetBeansProjects\Server\build
Updating property file: C:\Users\paolo2\Documents\NetBeansProjects\Server\build\built-jar.properties
Created dir: C:\Users\paolo2\Documents\NetBeansProjects\Server\build\classes
Created dir: C:\Users\paolo2\Documents\NetBeansProjects\Server\build\empty
Created dir: C:\Users\paolo2\Documents\NetBeansProjects\Server\build\generated-sources\ap-source-output
Compiling 4 source files to C:\Users\paolo2\Documents\NetBeansProjects\Server\build\classes
Note: Some input files use unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
compile:
Created dir: C:\Users\paolo2\Documents\NetBeansProjects\Server\dist
Copying 1 file to C:\Users\paolo2\Documents\NetBeansProjects\Server\build
Not copying library C:\Users\paolo2\Documents\NetBeansProjects\Server\dist\lib\sqlite-jdbc-3.7.2.jar , it can't be read.
Copy libraries to C:\Users\paolo2\Documents\NetBeansProjects\Server\dist\lib.
Building jar: C:\Users\paolo2\Documents\NetBeansProjects\Server\dist\Server.jar
To run this application from the command line without Ant, try:
java -jar "C:\Users\paolo2\Documents\NetBeansProjects\Server\dist\Server.jar"
jar:
BUILD SUCCESSFUL (total time: 7 seconds)
也许问题是没有包含的sqlite-jdbc-3.7.2.jar...我曾经手动添加它，但可能因为它不起作用。