File	Doc	Category	Size	Date	Package
DexFile.java	API Doc	Android 1.5 API	9656	Wed May 06 22:41:02 BST 2009	dalvik.system

DexFile

• java.lang.Object

Fields Summary
private final int	mCookie
private String	mFileName

Constructors Summary
public DexFile(File file) Opens a DEX file from a given File object. This will usually be a ZIP/JAR file with a "classes.dex" inside. The method should not be used for files inside the Dalvik cache. cts What will happen if we refer to the Dalvik cache? Should be either specified or throw an exception... param file the File object referencing the actual DEX file throws IOException if an I/O error occurs, such as the file not being found or access rights missing for opening it this(file.getPath());
public DexFile(String fileName) Opens a DEX file from a given filename. This will usually be a ZIP/JAR file with a "classes.dex" inside. The method should not be used for files inside the Dalvik cache. cts What will happen if we refer to the Dalvik cache? Should be either specified or throw an exception... param fileName the filename of the DEX file throws IOException if an I/O error occurs, such as the file not being found or access rights missing for opening it String wantDex = System.getProperty("android.vm.dexfile", "false"); if (!wantDex.equals("true")) throw new UnsupportedOperationException("No dex in this VM"); mCookie = openDexFile(fileName, null, 0); mFileName = fileName; //System.out.println("DEX FILE cookie is " + mCookie);
private DexFile(String sourceName, String outputName, int flags) Opens a DEX file from a given filename, using a specified file to hold the optimized data. param sourceName Jar or APK file with "classes.dex". param outputName File that will hold the optimized form of the DEX data. param flags Enable optional features. String wantDex = System.getProperty("android.vm.dexfile", "false"); if (!wantDex.equals("true")) throw new UnsupportedOperationException("No dex in this VM"); mCookie = openDexFile(sourceName, outputName, flags); mFileName = sourceName; //System.out.println("DEX FILE cookie is " + mCookie);

Methods Summary
public void	close() Closes the DEX file. This may not be able to release any resources. If classes have been loaded, the underlying storage can't be discarded. throws IOException if an I/O error occurs during closing the file, which normally should not happen cts Second sentence is a bit cryptic. closeDexFile(mCookie);
private static native void	closeDexFile(int cookie)
private static native java.lang.Class	defineClass(java.lang.String name, java.lang.ClassLoader loader, int cookie, java.security.ProtectionDomain pd)
public java.util.Enumeration	entries() Enumerate the names of the classes in this DEX file. return an enumeration of names of classes contained in the DEX file, in the usual internal form (like "java/lang/String"). return new DFEnum(this);
protected void	finalize() Called when the class is finalized. Makes sure the DEX file is closed. throws IOException if an I/O error occurs during closing the file, which normally should not happen close();
private static native java.lang.String[]	getClassNameList(int cookie)
public java.lang.String	getName() Gets the name of the (already opened) DEX file. return the file name return mFileName;
public static native boolean	isDexOptNeeded(java.lang.String fileName) Returns true if the VM believes that the apk/jar file is out of date and should be passed through "dexopt" again. param fileName the absolute path to the apk/jar file to examine. return true if dexopt should be called on the file, false otherwise. throws java.io.FileNotFoundException if fileName is not readable, not a file, or not present. throws java.io.IOException if fileName is not a valid apk/jar file or if problems occur while parsing it. throws java.lang.NullPointerException if fileName is null. throws dalvik.system.StaleDexCacheError if the optimized dex file is stale but exists on a read-only partition.
public java.lang.Class	loadClass(java.lang.String name, java.lang.ClassLoader loader) Loads a class. Returns the class on success, or a {@code null} reference on failure. If you are not calling this from a class loader, this is most likely not going to do what you want. Use {@link Class#forName(String)} instead. The method does not throw {@link ClassNotFoundException} if the class isn't found because it isn't feasible to throw exceptions wildly every time a class is not found in the first DEX file we look at. It will throw exceptions for other failures, though. param name the class name, which should look like "java/lang/String" param loader the class loader that tries to load the class (in most cases the caller of the method return the {@link Class} object representing the class, or {@code null} if the class cannot be loaded cts Exception comment is a bit cryptic. What exception will be thrown? return defineClass(name, loader, mCookie, null); //new ProtectionDomain(name) /*DEBUG ONLY*/);
public static dalvik.system.DexFile	loadDex(java.lang.String sourcePathName, java.lang.String outputPathName, int flags) Open a DEX file, specifying the file in which the optimized DEX data should be written. If the optimized form exists and appears to be current, it will be used; if not, the VM will attempt to regenerate it. This is intended for use by applications that wish to download and execute DEX files outside the usual application installation mechanism. This function should not be called directly by an application; instead, use a class loader such as dalvik.system.DexClassLoader. param sourcePathName Jar or APK file with "classes.dex". (May expand this to include "raw DEX" in the future.) param outputPathName File that will hold the optimized form of the DEX data. param flags Enable optional features. (Currently none defined.) return A new or previously-opened DexFile. throws IOException If unable to open the source or output file. /* * TODO: we may want to cache previously-opened DexFile objects. * The cache would be synchronized with close(). This would help * us avoid mapping the same DEX more than once when an app * decided to open it multiple times. In practice this may not * be a real issue. */ return new DexFile(sourcePathName, outputPathName, flags);
private static native int	openDexFile(java.lang.String sourceName, java.lang.String outputName, int flags)