| Package | Description | 
|---|---|
| java.lang.instrument | Provides services that allow Java programming language agents to instrument programs running on the JVM. | 
| java.net | Provides the classes for implementing networking applications. | 
| java.util.jar | Provides classes for reading and writing the JAR (Java ARchive) file
format, which is based on the standard ZIP file format with an
optional manifest file. | 
| Class and Description | 
|---|
| JarFile The  JarFileclass is used to read the contents of a jar file
 from any file that can be opened withjava.io.RandomAccessFile. | 
| Class and Description | 
|---|
| Attributes The Attributes class maps Manifest attribute names to associated string
 values. | 
| JarEntry This class is used to represent a JAR file entry. | 
| JarFile The  JarFileclass is used to read the contents of a jar file
 from any file that can be opened withjava.io.RandomAccessFile. | 
| Manifest The Manifest class is used to maintain Manifest entry names and their
 associated Attributes. | 
| Class and Description | 
|---|
| Attributes The Attributes class maps Manifest attribute names to associated string
 values. | 
| Attributes.Name The Attributes.Name class represents an attribute name stored in
 this Map. | 
| JarEntry This class is used to represent a JAR file entry. | 
| JarFile The  JarFileclass is used to read the contents of a jar file
 from any file that can be opened withjava.io.RandomAccessFile. | 
| JarInputStream The  JarInputStreamclass is used to read the contents of
 a JAR file from any input stream. | 
| JarOutputStream The  JarOutputStreamclass is used to write the contents
 of a JAR file to any output stream. | 
| Manifest The Manifest class is used to maintain Manifest entry names and their
 associated Attributes. | 
| Pack200.Packer The packer engine applies various transformations to the input JAR file,
 making the pack stream highly compressible by a compressor such as
 gzip or zip. | 
| Pack200.Unpacker The unpacker engine converts the packed stream to a JAR file. | 
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