| layout | class | title | summary |
|---|---|---|---|
default |
Header |
Import-Package ::= import ( ',' import )* |
The Import-Package header declares the imported packages for this bundle. |
The Import-Package header lists the packages that are required by the contained packages. The default for this header is *, resulting in importing all referred packages. This header therefore rarely has to be specified. However, in certain cases there is an unwanted import. The import is caused by code that the author knows can never be reached. This import can be removed by using a negating pattern. A pattern is inserted in the import as an extra import when it contains no wildcards and there is no referral to that package. This can be used to add an import statement for a package that is not referred to by your code but is still needed, for example, because the class is loaded by name.
For example:
Import-Package: !org.apache.commons.log4j, com.acme.*,\
com.foo.extra
During processing, bnd will attempt to find the exported version of imported packages. If no version or version range is specified on the import instruction, the exported version will then be used though the micro part and the qualifier are dropped. That is, when the exporter is 1.2.3.build123, then the import version will be 1.2. If a specific version (range) is specified, this will override any found version. This default an be overridden with the -versionpolicy instruction.
If an explicit version is given, then ${@} can be used to substitute the found version in a range. In those cases, the range macro can be very useful to calculate ranges and drop specific parts of the version. For example:
Import-Package: org.osgi.framework;version="[1.3,2.0)"
Import-Package: org.osgi.framework;version="${@}"
Import-Package: org.osgi.framework;version="${range;[==,=+);${@}}"
You can reference the Bundle-SymbolicName and Bundle-Version of the exporter on the classpath by using the ${@bundlesymbolicname} and ${@bundleversion} values. In those cases, the range macro can be very useful to calculate ranges and drop specific parts of the bundle version. For example:
Import-Package: org.eclipse.jdt.ui;bundle-symbolic-name="${@bundlesymbolicname}";\
bundle-version="${range;[==,+);${@bundleversion}}"
Packages with directive resolution:=dynamic will be removed from Import-Package and added to the DynamicImport-Package header after being processed like any other Import-Package entry. For example:
Import-Package: org.slf4j.*;resolution:=dynamic, *
If an imported package uses mandatory attributes, then bnd will attempt to add those attributes to the import statement. However, in certain (bizarre!) cases this is not wanted. It is therefore possible to remove an attribute from the import clause. This is done with the -remove-attribute directive or by setting the value of an attribute to !. The parameter of the -remove-attribute directive is an instruction and can use the standard options with !, *, ?, etc.
Import-Package: org.eclipse.core.runtime;-remove-attribute:="common",*
Or
Import-Package: org.eclipse.core.runtime;common=!,*
Directives that are not part of the OSGi specification will give a warning unless they are prefixed with x-.