Package org.apache.derby.impl.services.reflect

Class JarLoader

  • final class JarLoader
extends java.security.SecureClassLoader

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private StorageFile installedJar
      Handle to the installed jar file.
      private boolean isStream
      True if the jar can only be accessed using a stream, because the jar is itself in a database jar.
      private java.util.jar.JarFile jar
      When the jar file can be manipulated as a java.util.JarFile this holds the reference to the open jar.
      private java.lang.String[] name
      Two part name for the jar file.
      private UpdateLoader updateLoader  
      private HeaderPrintWriter vs  

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      (package private) java.lang.Class checkLoaded​(java.lang.String className, boolean resolve)  
      (package private) java.lang.String getJarName()
      Return the SQL name for the installed jar.
      private java.io.InputStream getRawStream​(java.io.InputStream in, java.lang.String name)
      Get a stream from a zip file that is itself a stream.
      private java.io.InputStream getRawStream​(java.lang.String name)
      Get a stream for a resource directly from a JarFile.
      java.io.InputStream getResourceAsStream​(java.lang.String name)  
      private java.security.cert.Certificate[] getSigners​(java.lang.String className, java.util.jar.JarEntry je)
      Validate the security certificates (signers) for the class data.
      (package private) java.io.InputStream getStream​(java.lang.String name)
      Get an InputStream for the given resource.
      private java.lang.SecurityException handleException​(java.lang.Exception e, java.lang.String className)
      Provide a SecurityManager with information about the class name and the jar file.
      (package private) void initialize()
      Initialize the class loader so it knows if it is loading from a ZipFile or an InputStream
      protected java.lang.Class loadClass​(java.lang.String className, boolean resolve)
      Handle all requests to the top-level loader.
      private java.lang.Class loadClassData​(java.io.InputStream in, java.lang.String className, java.lang.String jvmClassName, boolean resolve)
      Load the class data when the installed jar is accessible only as an input stream (the jar is itself in a database jar).
      (package private) java.lang.Class loadClassData​(java.lang.String className, java.lang.String jvmClassName, boolean resolve)  
      private java.lang.Class loadClassData​(java.util.jar.JarEntry e, java.io.InputStream in, java.lang.String className, boolean resolve)
      Load and optionally resolve the class given its JarEntry and an InputStream to the class fiel format.
      private java.lang.Class loadClassDataFromJar​(java.lang.String className, java.lang.String jvmClassName, boolean resolve)
      Load the class data when the installed jar is accessible as a java.util.jarFile.
      (package private) byte[] readData​(java.util.jar.JarEntry ze, java.io.InputStream in, java.lang.String className)
      Read the raw data for the class file format into a byte array that can be used for loading the class.
      (package private) void setInvalid()
      Set this loader to be invaid so that it will not resolve any classes or resources.
      java.lang.String toString()
      Return the jar name if toString() is called on this class loader.

      • Methods inherited from class java.security.SecureClassLoader

        defineClass, defineClass, getPermissions

      • Methods inherited from class java.lang.ClassLoader

        clearAssertionStatus, defineClass, defineClass, defineClass, defineClass, definePackage, findClass, findClass, findLibrary, findLoadedClass, findResource, findResource, findResources, findSystemClass, getClassLoadingLock, getDefinedPackage, getDefinedPackages, getName, getPackage, getPackages, getParent, getPlatformClassLoader, getResource, getResources, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, getUnnamedModule, isRegisteredAsParallelCapable, loadClass, registerAsParallelCapable, resolveClass, resources, setClassAssertionStatus, setDefaultAssertionStatus, setPackageAssertionStatus, setSigners

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

    • Field Detail

      • name

        private final java.lang.String[] name
        Two part name for the jar file.

      • installedJar

        private StorageFile installedJar
        Handle to the installed jar file.

      • jar

        private java.util.jar.JarFile jar
        When the jar file can be manipulated as a java.util.JarFile this holds the reference to the open jar. When the jar can only be manipulated as an InputStream (because the jar is itself in a database jar) then this will be null.

      • isStream

        private boolean isStream
        True if the jar can only be accessed using a stream, because the jar is itself in a database jar. When fals the jar is accessed using the jar field.

    • Method Detail

      • initialize

        void initialize()
        Initialize the class loader so it knows if it is loading from a ZipFile or an InputStream

      • loadClass

        protected java.lang.Class loadClass​(java.lang.String className,
                                    boolean resolve)
                             throws java.lang.ClassNotFoundException
        Handle all requests to the top-level loader.
        Overrides:
        loadClass in class java.lang.ClassLoader
        Throws:
        java.lang.ClassNotFoundException - Class can not be found

      • getResourceAsStream

        public java.io.InputStream getResourceAsStream​(java.lang.String name)
        Overrides:
        getResourceAsStream in class java.lang.ClassLoader

      • getJarName

        final java.lang.String getJarName()
        Return the SQL name for the installed jar. Used for error and informational messages.

      • loadClassData

        java.lang.Class loadClassData​(java.lang.String className,
                              java.lang.String jvmClassName,
                              boolean resolve)

      • getStream

        java.io.InputStream getStream​(java.lang.String name)
        Get an InputStream for the given resource.

      • loadClassDataFromJar

        private java.lang.Class loadClassDataFromJar​(java.lang.String className,
                                             java.lang.String jvmClassName,
                                             boolean resolve)
                                      throws java.io.IOException
        Load the class data when the installed jar is accessible as a java.util.jarFile.
        Throws:
        java.io.IOException

      • loadClassData

        private java.lang.Class loadClassData​(java.io.InputStream in,
                                      java.lang.String className,
                                      java.lang.String jvmClassName,
                                      boolean resolve)
                               throws java.io.IOException
        Load the class data when the installed jar is accessible only as an input stream (the jar is itself in a database jar).
        Throws:
        java.io.IOException

      • loadClassData

        private java.lang.Class loadClassData​(java.util.jar.JarEntry e,
                                      java.io.InputStream in,
                                      java.lang.String className,
                                      boolean resolve)
                               throws java.io.IOException
        Load and optionally resolve the class given its JarEntry and an InputStream to the class fiel format. This is common code for when the jar is accessed directly using JarFile or through InputStream.
        Throws:
        java.io.IOException

      • checkLoaded

        java.lang.Class checkLoaded​(java.lang.String className,
                            boolean resolve)

      • setInvalid

        void setInvalid()
        Set this loader to be invaid so that it will not resolve any classes or resources.

      • getRawStream

        private java.io.InputStream getRawStream​(java.lang.String name)
        Get a stream for a resource directly from a JarFile. In this case we can safely return the stream directly. It's a new stream set up by the zip code to read just the contents of this entry.

      • getRawStream

        private java.io.InputStream getRawStream​(java.io.InputStream in,
                                         java.lang.String name)
        Get a stream from a zip file that is itself a stream. We copy to the contents to a byte array and return a stream around that to the caller. Though a copy is involved it has the benefit of:
        • Isolating the application from the JarInputStream, thus denying any possibility of the application reading more of the jar that it should be allowed to. E.g. the contents class files are not exposed through getResource.
        • Avoids any possibility of the application holding onto the open stream beyond shutdown of the database, thus leading to leaked file descriptors or inability to remove the jar.

      • readData

        byte[] readData​(java.util.jar.JarEntry ze,
                java.io.InputStream in,
                java.lang.String className)
         throws java.io.IOException
        Read the raw data for the class file format into a byte array that can be used for loading the class. If this is a signed class and it has been compromised then a SecurityException will be thrown.
        Throws:
        java.io.IOException

      • getSigners

        private java.security.cert.Certificate[] getSigners​(java.lang.String className,
                                                    java.util.jar.JarEntry je)
                                             throws java.io.IOException
        Validate the security certificates (signers) for the class data.
        Throws:
        java.io.IOException

      • handleException

        private java.lang.SecurityException handleException​(java.lang.Exception e,
                                                    java.lang.String className)
        Provide a SecurityManager with information about the class name and the jar file.

      • toString

        public java.lang.String toString()
        Return the jar name if toString() is called on this class loader.
        Overrides:
        toString in class java.lang.Object