Hi all,
I am working with H2 java database that allows to create triggers from java
source code.
To compile the trigger the following code is used:
JavaCompiler JAVA_COMPILER = ToolProvider.getSystemJavaCompiler();
String fullClassName = packageName + "." + className;
StringWriter writer = new StringWriter();
try (JavaFileManager fileManager = new
ClassFileManager(JAVA_COMPILER
.getStandardFileManager(null, null, null))) {
ArrayList<JavaFileObject> compilationUnits = new ArrayList<>();
compilationUnits.add(new StringJavaFileObject(fullClassName, source));
// cannot concurrently compile
final boolean ok;
synchronized (JAVA_COMPILER) {
ok = JAVA_COMPILER.getTask(writer, fileManager, null, null,
null, compilationUnits).call();
}
String output = writer.toString();
handleSyntaxError(output, (ok? 0: 1));
return fileManager.getClassLoader(null).loadClass(fullClassName);
} catch (ClassNotFoundException | IOException e) {
throw DbException.convert(e);
}
Trigger `fullClassName` = `org.h2.dynamic.trigger.SOME_TRIGGER`.
And the trigger `source` =
package org.h2.dynamic.trigger;
import java.util.*;
import java.math.*;
import java.sql.*;
public class SOME_TRIGGER {
public static org.h2.api.Trigger create() {
return new org.h2.api.Trigger() {
@Override
public void init(Connection conn, String schemaName, String
triggerName,
String tableName, boolean before, int type) throws
SQLException { }
@Override
public void fire(Connection conn, Object[] oldRow, Object[] newRow)
throws SQLException { }
@Override
public void close() throws SQLException { }
@Override
public void remove() throws SQLException { }
};
}
}
When H2 is on classpath I don't have any problems - trigger is compiled.
However, when H2 is on
module path (H2 has in manifest Automatic-Module-Name: com.h2database) on some
of child layers
(not boot layer) I get the following `output`:
/org/h2/dynamic/trigger/SOME_TRIGGER.java:6: error: package org.h2.api does
not exist
public static org.h2.api.Trigger create() {
^
1 error
As I understand the problem is with classloader and JavaCompiler. Could anyone
say how it can be fixed?
Best regards, Alex
