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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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package com.sun.tools.sjavac;

import java.io.Writer;
import java.net.URI;
import java.util.Map;
import java.util.Set;

import com.sun.tools.sjavac.comp.CompilationService;
import com.sun.tools.sjavac.options.Options;
import com.sun.tools.sjavac.pubapi.PubApi;

The transform interface is used to transform content inside a package, from one form to another.
Usually the output form is an unpredictable number of output files. (eg class files)
but can also be an unpredictable number of generated source files (eg idl2java)
or a single predictable output file (eg when copying,cleaning or compiling a properties file).
 
This is NOT part of any supported API.
 If you write code that depends on this, you do so at your own risk.
 This code and its internal interfaces are subject to change or
 deletion without notice.
/**
 * The transform interface is used to transform content inside a package, from one form to another.
 * Usually the output form is an unpredictable number of output files. (eg class files)
 * but can also be an unpredictable number of generated source files (eg idl2java)
 * or a single predictable output file (eg when copying,cleaning or compiling a properties file).
 *
 *  <p><b>This is NOT part of any supported API.
 *  If you write code that depends on this, you do so at your own risk.
 *  This code and its internal interfaces are subject to change or
 *  deletion without notice.</b>
 */
public interface Transformer {
    
The transform method takes a set of package names, mapped to their source files and to the
pubapis of the packages.
The transform implementation must:
   store the names of the generated artifacts for each package into package_artifacts
   store found dependencies to other packages into the supplied set package_dependencies
   store the public api for a package into the supplied set package_pubapis
Any benign messages as a result of running the transform
are written into stdout, and errors are written to stderr.
The debug_level can be 0=silent (only warnings and errors) 1=normal 2=verbose 3 or greater=debug
setExtra is used to set the extra information information that can be passed on
the command line to the smart javac wrapper.
If sjavac is building incrementally from an existing javac_state, the var incremental is true.
The transformer will only be called if some source in the package (or dependency) has
a modified timestamp. Thus the transformer might get called with many sources, of which
only one has changed. The transformer is allowed to regenerate all artifacts but
a better transformer will only write those artifacts that need updating.
However the transformer must verify that the existing artifacts really are there!
and it must always update package_artifacts, package_dependencies, and package_pubapis correctly.
This means that at least for Java source, it will always have to recompile the sources.
The transformer is allowed to put files anywhere in the dest_root.
An example of this is, can be the META-INF transformer that copy files
below META-INF directories to the single META-INF directory below dest_root.
False is returned if there was an error that prevented the transform.
I.e. something was printed on stderr.
If num_cores is set to a non-zero value. The transform should attempt to use no more than these
number of threads for heavy work.
/**
     * The transform method takes a set of package names, mapped to their source files and to the
     * pubapis of the packages.
     *
     * The transform implementation must:
     *    store the names of the generated artifacts for each package into package_artifacts
     *    store found dependencies to other packages into the supplied set package_dependencies
     *    store the public api for a package into the supplied set package_pubapis
     *
     * Any benign messages as a result of running the transform
     * are written into stdout, and errors are written to stderr.
     *
     * The debug_level can be 0=silent (only warnings and errors) 1=normal 2=verbose 3 or greater=debug
     * setExtra is used to set the extra information information that can be passed on
     * the command line to the smart javac wrapper.
     *
     * If sjavac is building incrementally from an existing javac_state, the var incremental is true.
     *
     * The transformer will only be called if some source in the package (or dependency) has
     * a modified timestamp. Thus the transformer might get called with many sources, of which
     * only one has changed. The transformer is allowed to regenerate all artifacts but
     * a better transformer will only write those artifacts that need updating.
     *
     * However the transformer must verify that the existing artifacts really are there!
     * and it must always update package_artifacts, package_dependencies, and package_pubapis correctly.
     * This means that at least for Java source, it will always have to recompile the sources.
     *
     * The transformer is allowed to put files anywhere in the dest_root.
     * An example of this is, can be the META-INF transformer that copy files
     * below META-INF directories to the single META-INF directory below dest_root.
     *
     * False is returned if there was an error that prevented the transform.
     * I.e. something was printed on stderr.
     *
     * If num_cores is set to a non-zero value. The transform should attempt to use no more than these
     * number of threads for heavy work.
     */
    boolean transform(CompilationService sjavac,
                      Map<String,Set<URI>> pkgSrcs,
                      Set<URI>             visibleSources,
                      Map<String,Set<String>> oldPackageDependencies,
                      URI destRoot,
                      Map<String,Set<URI>>    packageArtifacts,
                      Map<String, Map<String, Set<String>>> packageDependencies,   // Package name -> Fully Qualified Type [from] -> Set of fully qualified type [to]
                      Map<String, Map<String, Set<String>>> packageCpDependencies, // Package name -> Fully Qualified Type [from] -> Set of fully qualified type [to]
                      Map<String, PubApi>     packagePublicApis,
                      Map<String, PubApi>     dependencyApis,
                      int debugLevel,
                      boolean incremental,
                      int numCores);

    void setExtra(String e);
    void setExtra(Options args);
}