Fix javac --incremental by using jmake for dependency analysis

third_party/jmake/src/org/pantsbuild/jmake/RefClassFinder.java

Index: third_party/jmake/src/org/pantsbuild/jmake/RefClassFinder.java
diff --git a/third_party/jmake/src/org/pantsbuild/jmake/RefClassFinder.java b/third_party/jmake/src/org/pantsbuild/jmake/RefClassFinder.java
new file mode 100644
index 0000000000000000000000000000000000000000..58c8884ab55b445e2e71cd51d44f3f62a887536a
--- /dev/null
+++ b/third_party/jmake/src/org/pantsbuild/jmake/RefClassFinder.java
@@ -0,0 +1,697 @@
+/* Copyright (c) 2002-2008 Sun Microsystems, Inc. All rights reserved
+ *
+ * This program is distributed under the terms of
+ * the GNU General Public License Version 2. See the LICENSE file
+ * at the top of the source tree.
+ */
+package org.pantsbuild.jmake;
+
+import java.lang.reflect.Modifier;
+import java.util.LinkedHashSet;
+import java.util.Set;
+
+/**
+ * This class implements finding classes referencing other classes and members in various ways.
+ *
+ * @author Misha Dmitriev
+ * 12 March 2004
+ */
+public class RefClassFinder {
+
+    private boolean failOnDependentJar;   // If true, will fail if a dependency of a sourceless class
+    // (coming from a .jar) on a "normal" class is detected
+    private boolean noWarnOnDependentJar; // If true, not even a warning will be issued in the above case.
+    private String checkedClassName;
+    private PCDManager pcdm;
+    private Set<String> affectedClassNames;
+    private boolean checkedClassIsFromJar;
+
+    /** An instance of RefClassFinder is created once per session, passing it the global options that do not change */
+    public RefClassFinder(PCDManager pcdm, boolean failOnDependentJar, boolean noWarnOnDependentJar) {
+        this.pcdm = pcdm;
+        this.failOnDependentJar = failOnDependentJar;
+        this.noWarnOnDependentJar = noWarnOnDependentJar;
+    }
+
+    /** This method is called every time we are going to check a new class */
+    public void initialize(String checkedClassName, boolean checkedClassIsFromJar) {
+        this.checkedClassName = checkedClassName;
+        this.checkedClassIsFromJar = checkedClassIsFromJar;
+        affectedClassNames = new LinkedHashSet<String>();
+    }
+
+    /**
+     * Returns the names of project classes that were found potentially affec
+     * by the changes to the checked class.
+     */
+    public String[] getAffectedClassNames() {
+        int size = affectedClassNames.size();
+        if (size == 0) {
+            return null;
+        } else {
+            String[] ret = new String[size];
+            int i = 0;
+            for (String className : affectedClassNames) {
+                ret[i++] = className;
+            }
+            return ret;
+        }
+    }
+
+    /**
+     * Find all project classes that can access field fieldNo of class fieldClassInfo.
+     * Used if a compile-time constant is changed.
+     */
+    public void findAllProjectClasses(ClassInfo fieldClassInfo, int fieldNo) {
+      for (PCDEntry pcde : pcdm.entries()) {
+            if (pcde.checkResult == PCDEntry.CV_DELETED) {
+                continue;
+            }
+            if (pcde.javaFileFullPath.endsWith(".jar")) {
+                continue;
+            }
+            ClassInfo clientInfo =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD, pcde);
+            if (clientInfo == null) {
+                continue;  // New class
+            }
+            if (memberAccessibleFrom(fieldClassInfo, fieldNo, clientInfo, true)) {
+                addToAffectedClassNames(clientInfo.name);
+            }
+        }
+    }
+
+    /**
+     * Find all project classes that reference class with the given name
+     * (but not its array class) directly from the constantpool.
+     */
+    public void findReferencingClasses0(ClassInfo classInfo) {
+        findReferencingClasses(classInfo, 0, false, null);
+    }
+
+
+    /* In the following "find...ReferencingClasses1" methods, "referencing C" means
+     * "referencing C or its array class directly from the constant pool, as a type of a data
+     * field, as a type in a method signature or a thrown exception, as a directly implemented
+     * interface or a direct superclass".
+     */
+    /** Used for deleted classes. */
+    public void findReferencingClassesForDeletedClass(ClassInfo classInfo) {
+        String packageName = classInfo.packageName;
+        boolean isPublic = classInfo.isPublic();
+        boolean isInterface = classInfo.isInterface();
+        for (PCDEntry pcde : pcdm.entries()) {
+            ClassInfo clientInfo =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD, pcde);
+            if (clientInfo == null) {
+                continue;  // New class
+            }
+            if (!isPublic && packageName.equals(clientInfo.packageName)) {
+                continue;
+            }
+            if (clientInfo.referencesClass(classInfo.name, isInterface, 1)) {
+                addToAffectedClassNames(clientInfo.name);
+            }
+        }
+
+    }
+
+    /**
+     * For the given class p.C, find each project class X referencing C, that is not a member of
+     * package p and is not a direct or indirect subclass of C's directly enclosing class.
+     * (public -&gt; protected transformation)
+     */
+    public void findDiffPackageAndNotSubReferencingClasses1(ClassInfo classInfo) {
+        String packageName = classInfo.packageName;
+        String directlyEnclosingClass = classInfo.directlyEnclosingClass;
+        for (PCDEntry pcde : pcdm.entries()) {
+            ClassInfo clientInfo =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD, pcde);
+            if (clientInfo == null) {
+                continue;  // New class
+            }
+            if (packageName.equals(clientInfo.packageName) ||
+                    clientInfo.isSubclassOf(directlyEnclosingClass, false)) {
+                continue;
+            }
+            if (clientInfo.referencesClass(classInfo.name, classInfo.isInterface(), 1)) {
+                addToAffectedClassNames(clientInfo.name);
+            }
+        }
+    }
+
+    /**
+     * For class p.C, find each project class X referencing C, whose top level enclosing
+     * class is different from that of C.
+     * (public -&gt; private transformation)
+     */
+    public void findReferencingClasses1(ClassInfo classInfo) {
+        String topLevelEnclosingClass = classInfo.topLevelEnclosingClass;
+        for (PCDEntry pcde : pcdm.entries()) {
+            ClassInfo clientInfo =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD, pcde);
+            if (clientInfo == null) {
+                continue;  // New class
+            }
+            if (topLevelEnclosingClass.equals(clientInfo.topLevelEnclosingClass)) {
+                continue;
+            }
+            if (clientInfo.referencesClass(classInfo.name, classInfo.isInterface(), 1)) {
+                addToAffectedClassNames(clientInfo.name);
+            }
+        }
+    }
+
+    /**
+     * For class p.C, find each project class X referencing C, whose direct or indirect superclass
+     * is C's directly enclosing class, or which is a member of package p, whose top level enclosing
+     * class is different from that of C.
+     * (protected -&gt; private transformation)
+     */
+    public void findThisPackageOrSubReferencingClasses1(ClassInfo classInfo) {
+        String directlyEnclosingClass = classInfo.directlyEnclosingClass;
+        String topLevelEnclosingClass = classInfo.topLevelEnclosingClass;
+        String packageName = classInfo.packageName;
+      for (PCDEntry entry : pcdm.entries()) {
+            ClassInfo clientInfo =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD, entry);
+            if (clientInfo == null) {
+                continue;  // New class
+            }
+            if ((!clientInfo.packageName.equals(packageName)) &&
+                    !clientInfo.isSubclassOf(directlyEnclosingClass, false)) {
+                continue;
+            }
+            if (clientInfo.topLevelEnclosingClass.equals(topLevelEnclosingClass)) {
+                continue;
+            }
+            if (clientInfo.referencesClass(classInfo.name, classInfo.isInterface(), 1)) {
+                addToAffectedClassNames(clientInfo.name);
+            }
+        }
+    }
+
+    /**
+     * For class p.C, find each project class X referencing C, which is a member of package p and whose
+     * top level enclosing class is different from that of C.
+     * (default -&gt; private transformation)
+     */
+    public void findThisPackageReferencingClasses1(ClassInfo classInfo) {
+        String topLevelEnclosingClass = classInfo.topLevelEnclosingClass;
+        String packageName = classInfo.packageName;
+        for (PCDEntry entry : pcdm.entries()) {
+            ClassInfo clientInfo =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD,
+                        entry);
+            if (clientInfo == null) {
+                continue;  // New class
+            }
+            if (!clientInfo.packageName.equals(packageName)) {
+                continue;
+            }
+            if (topLevelEnclosingClass.equals(clientInfo.topLevelEnclosingClass)) {
+                continue;
+            }
+            if (clientInfo.referencesClass(classInfo.name, classInfo.isInterface(), 1)) {
+                addToAffectedClassNames(clientInfo.name);
+            }
+        }
+    }
+
+    /**
+     * For class p.C, find each project class X referencing C, which is not a member of package p.
+     * (public -&gt; default transformation)
+     */
+    public void findDiffPackageReferencingClasses1(ClassInfo classInfo) {
+        String packageName = classInfo.packageName;
+        for (PCDEntry pcde : pcdm.entries()) {
+            ClassInfo clientInfo =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD, pcde);
+            if (clientInfo == null) {
+                continue;  // New class
+            }
+            if (clientInfo.packageName.equals(packageName)) {
+                continue;
+            }
+            if (clientInfo.referencesClass(classInfo.name, classInfo.isInterface(), 1)) {
+                addToAffectedClassNames(clientInfo.name);
+            }
+        }
+    }
+
+    /**
+     * For class p.C, find each project class X referencing C, which is not a member of package p and
+     * whose direct or indirect superclass is C's directly enclosing class.
+     * (protected -&gt; default transformation)
+     */
+    public void findDiffPackageAndSubReferencingClasses1(ClassInfo classInfo) {
+        String packageName = classInfo.packageName;
+        String directlyEnclosingClass = classInfo.directlyEnclosingClass;
+      for (PCDEntry pcde : pcdm.entries()) {
+            ClassInfo clientInfo =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD, pcde);
+            if (clientInfo == null) {
+                continue;  // New class
+            }
+            if (clientInfo.packageName.equals(packageName)) {
+                continue;
+            }
+            if (!clientInfo.isSubclassOf(directlyEnclosingClass, false)) {
+                continue;
+            }
+            if (clientInfo.referencesClass(classInfo.name, classInfo.isInterface(), 1)) {
+                addToAffectedClassNames(clientInfo.name);
+            }
+        }
+    }
+
+    /**
+     * Find all project classes that reference both of the classes with the
+     * given names (or array classes of one or both) directly or indirectly from the
+     * constantpool, as a type of a data field, as a type in a method signature or a
+     * thrown exception, as a directly/indirectly implemented interface or a
+     * direct/indirect superclass.
+     */
+    public void findReferencingClasses2(ClassInfo classInfo1, ClassInfo classInfo2) {
+        Set<String> refClazz1 = new LinkedHashSet<String>();
+        findReferencingClasses(classInfo1, 2, false, refClazz1);
+        Set<String> refClazz2 = new LinkedHashSet<String>();
+        findReferencingClasses(classInfo2, 2, false, refClazz2);
+
+        for (String className1 : refClazz1) {
+            if (refClazz2.contains(className1)) {
+                addToAffectedClassNames(className1);
+            }
+        }
+    }
+
+    /** Find all project classes which are direct subclasses of the given class */
+    public void findDirectSubclasses(ClassInfo classInfo) {
+        for (ClassInfo subclassInfo : classInfo.getDirectSubclasses()) {
+            addToAffectedClassNames(subclassInfo.name);
+        }
+    }
+
+    /**
+     * Find all non-abstract project classes that implement the given interface or any of its
+     * subclasses directly, and all non-abstract classes that are direct descendants of abstract
+     * classes that implement the given interface directly or indirectly. Class C implements
+     * interface I indirectly, if C or some superclass of C directly implements I or some sublcass of I.
+     */
+    public void findDirectlyAndOtherwiseImplementingConcreteClasses(ClassInfo intfInfo) {
+        for (PCDEntry entry : pcdm.entries()) {
+            ClassInfo clientInfo =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD, entry);
+            if (clientInfo == null) {
+                continue;  // New class
+            }
+            if (clientInfo.isInterface()) {
+                continue;
+            }
+            if (clientInfo.isAbstract()) {
+                if (clientInfo.implementsInterfaceDirectlyOrIndirectly(intfInfo.name)) {
+                    findAllNearestConcreteSubclasses(clientInfo);
+                }
+            } else {
+                if (clientInfo.implementsIntfOrSubintfDirectly(intfInfo.name)) {
+                    addToAffectedClassNames(clientInfo.name);
+                }
+            }
+        }
+    }
+
+    private void findAllNearestConcreteSubclasses(ClassInfo classInfo) {
+        for (ClassInfo subclassInfo : classInfo.getDirectSubclasses()) {
+            if (subclassInfo.isAbstract()) {
+                findAllNearestConcreteSubclasses(subclassInfo);
+            } else {
+                addToAffectedClassNames(subclassInfo.name);
+            }
+        }
+    }
+
+    /**
+     * Find all interfaces and abstract classes that implement the given interface and declare or inherit
+     * a method with the given name. For those that overload this method, find referencing classes.
+     */
+    public void findAbstractSubtypesWithSameNameMethod(ClassInfo intfInfo, String mName, final String mSig) {
+      for (PCDEntry pcde : pcdm.entries()) {
+            ClassInfo ci =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD, pcde);
+            if (ci == null) {
+                continue;  // New class or not in project
+            }
+            if (!(ci.isInterface() || ci.isAbstract())) {
+                continue;
+            }
+            if (ci.implementsInterfaceDirectlyOrIndirectly(intfInfo.name)) {
+                addToAffectedClassNames(ci.name);
+                // Check if the new method overloads an existing (declared or inherited) method. Overloading test is rough -
+                // we just check if the number of parameters is the same.
+                ci.findExistingSameNameMethods(mName, true, true, new ClassInfo.MethodHandler() {
+
+                    void handleMethod(ClassInfo classInfo, int otherMethodIdx) {
+                        String otherMSig =
+                                classInfo.methodSignatures[otherMethodIdx];
+                        if ( (!mSig.equals(otherMSig)) &&
+                                Utils.sameParamNumber(mSig, otherMSig)) {
+                            findReferencingClassesForMethod(classInfo, otherMethodIdx);
+                        }
+                    }
+                });
+            }
+        }
+    }
+
+    /** Find all project classes that reference the given field. */
+    public void findReferencingClassesForField(ClassInfo classInfo, int fieldNo) {
+        findReferencingClassesForMember(classInfo, fieldNo, true, false, false);
+    }
+
+    /**
+     * Find all project classes that reference the given field and which are in
+     * different packages.
+     */
+    public void findDiffPackageReferencingClassesForField(ClassInfo classInfo, int fieldNo) {
+        findReferencingClassesForMember(classInfo, fieldNo, true, true, false);
+    }
+
+    /**
+     * Find all project classes that reference the given field, which are in different
+     * packages and are direct or indirect subclasses of the member's declaring class
+     * (protected -&gt; default transformation).
+     */
+    public void findDiffPackageAndSubReferencingClassesForField(ClassInfo classInfo, int fieldNo) {
+        findReferencingClassesForMember(classInfo, fieldNo, true, true, true);
+    }
+
+    /** Find all project classes that reference the given method. */
+    public void findReferencingClassesForMethod(ClassInfo classInfo, int methodNo) {
+        findReferencingClassesForMember(classInfo, methodNo, false, false, false);
+    }
+
+    /**
+     * Find all project classes that reference the given method and which are in
+     * different packages.
+     */
+    public void findDiffPackageReferencingClassesForMethod(ClassInfo classInfo, int methodNo) {
+        findReferencingClassesForMember(classInfo, methodNo, false, true, false);
+    }
+
+    /**
+     * Find all project classes that reference the given method, which are in different
+     * packages and are direct or indirect subclasses of the member's declaring class
+     * (protected -&gt; default transformation)
+     */
+    public void findDiffPackageAndSubReferencingClassesForMethod(ClassInfo classInfo, int methodNo) {
+        findReferencingClassesForMember(classInfo, methodNo, false, true, true);
+    }
+
+    /**
+     * Find all project classes that re-implement the given method and that are
+     * direct/indirect subclasses of this method's declaring class. If some subclass C
+     * re-implements the given method, we don't have to search C's subclasses further.
+     */
+    public void findSubclassesReimplementingMethod(ClassInfo classInfo, int methodNo) {
+        findSubclassesReimplementingMethod(classInfo, classInfo, methodNo);
+    }
+
+    private void findSubclassesReimplementingMethod(ClassInfo targetClass, ClassInfo methodDeclaringClass, int methodNo) {
+        for (ClassInfo subclass : targetClass.getDirectSubclasses()) {
+            if (subclass.declaresMethod(methodDeclaringClass, methodNo)) {
+                addToAffectedClassNames(subclass.name);
+            } else {
+                findSubclassesReimplementingMethod(subclass, methodDeclaringClass, methodNo);
+            }
+        }
+    }
+
+    /**
+     * For a given class C, find all concrete direct subclasses, and all direct concrente subclasses of C's direct
+     * or indirect abstract subclasses.
+     */
+    public void findConcreteSubclasses(ClassInfo targetClass) {
+        for (ClassInfo subclass : targetClass.getDirectSubclasses()) {
+            if (subclass.isAbstract()) {
+                findConcreteSubclasses(subclass);
+            } else {
+                addToAffectedClassNames(subclass.name);
+            }
+        }
+    }
+
+    /**
+     * Find any concrete subclasses of targetClass that don't override or inherit a concrete implementation
+     * of the given method.
+     */
+    public void findConcreteSubclassesNotOverridingAbstractMethod(ClassInfo targetClass, ClassInfo methodDeclaringClass, int methodNo) {
+        for (ClassInfo subclass : targetClass.getDirectSubclasses()) {
+            int pos =
+                    subclass.getDeclaredMethodPos(methodDeclaringClass, methodNo);
+            if (pos == -1) { // This method is not overridden in this class
+                if (!subclass.isAbstract()) {
+                    addToAffectedClassNames(subclass.name);
+                } else {
+                    findConcreteSubclassesNotOverridingAbstractMethod(subclass, methodDeclaringClass, methodNo);
+                }
+            } else { // A chance that this method is declared abstract once again...
+                if (Modifier.isAbstract(subclass.methodAccessFlags[pos])) {
+                    findConcreteSubclassesNotOverridingAbstractMethod(subclass, methodDeclaringClass, methodNo);
+                }
+            }
+        }
+    }
+
+    /** Find all project classes that reference any method that throws the given exception. */
+    public void findRefsToMethodsThrowingException(ClassInfo excClassInfo) {
+            for (PCDEntry pcde : pcdm.entries()) {
+            ClassInfo classInfo =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD, pcde);
+            if (classInfo == null) {
+                continue;  // New class
+            }
+            int methodIdx = -1;
+            do {
+                methodIdx =
+                        classInfo.hasMethodThrowingException(excClassInfo, methodIdx + 1);
+                if (methodIdx != -1) {
+                    findReferencingClassesForMethod(classInfo, methodIdx);
+                }
+            } while (methodIdx != -1);
+        }
+    }
+
+    /**
+     * Find all project classes declaring a static field with the given name. Currently used only to look up
+     * classes referencing given class X via the "X.class" construct.
+     */
+    public void findClassesDeclaringField(String name, String signature, boolean isStatic, String packageToLookIn) {
+      for (PCDEntry pcde : pcdm.entries()) {
+            ClassInfo classInfo =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD, pcde);
+            if (classInfo == null) {
+                continue;  // New class
+            }
+            if (packageToLookIn != null &&
+                    !classInfo.packageName.equals(packageToLookIn)) {
+                continue;
+            }
+            if (classInfo.declaresField(name, signature, isStatic)) {
+                addToAffectedClassNames(classInfo.name);
+            }
+        }
+    }
+
+    public void addToAffectedClassNames(String className) {
+        String res = pcdm.classAlreadyRecompiledOrUncompileable(className);
+        if (res == null) {
+            affectedClassNames.add(className);
+        } else if (!"".equals(res)) {  // The dependent class comes from a .jar.
+            if (checkedClassIsFromJar || noWarnOnDependentJar) {
+                return;
+            }
+            String message = "Class " + className + " is affected by a change to " + checkedClassName + ", but can't be recompiled, " +
+                    "since it is located in archive " + res;
+            if (failOnDependentJar) {
+                throw new PrivateException(new PublicExceptions.JarDependsOnSourceException(message));
+            } else {
+                Utils.printWarningMessage("Warning: " + message);
+            }
+        }
+    }
+
+    /**
+     * Find all project classes that reference the class with the given name.
+     * The second parameter controls the "thoroughness degree", and its value is passed to ClassInfo.referencesClass()
+     * method (see the comment to it). The fromDiffPackages parameter defines whether all such classes
+     * or only classes from different packages are required.
+     */
+    private void findReferencingClasses(ClassInfo classInfo,
+            int thorDegree, boolean fromDiffPackages,
+            Set<String> ret) {
+        String packageName = classInfo.packageName;
+        for (PCDEntry pcde : pcdm.entries()) {
+            ClassInfo clientInfo =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD, pcde);
+            if (clientInfo == null) {
+                continue;  // New class
+            }
+            if (fromDiffPackages && packageName.equals(clientInfo.packageName)) {
+                continue;
+            }
+            // If thorDegree == 2, i.e. indirect references from the constantpool (e.g. a reference to a method which
+            // has classInfo as one of its formal parameter types) are taken into account, then we should check all of
+            // the classes, whether classInfo is directly accessible from them or not.
+            if (thorDegree != 2 && (!classAccessibleFrom(classInfo, clientInfo))) {
+                continue;
+            }
+
+            if (clientInfo.referencesClass(classInfo.name, classInfo.isInterface(), thorDegree)) {
+                if (ret == null) {
+                    addToAffectedClassNames(clientInfo.name);
+                } else {
+                    ret.add(clientInfo.name);
+                }
+            }
+        }
+    }
+
+    /**
+     * Find all project classes that reference the given member. If fromDiffPackages
+     * is true, then only classes that do not belong to the package of the member's
+     * declaring class should be returned. If onlySubclasses is true, then only
+     * classes that are subclasses of member's declaring class should be returned.
+     */
+    private void findReferencingClassesForMember(ClassInfo declaringClassInfo, int memberNo,
+            boolean isField,
+            boolean fromDiffPackages, boolean onlySubclasses) {
+        String declaringClassName = declaringClassInfo.name;
+        String declaringClassPackage = declaringClassInfo.packageName;
+        for (PCDEntry pcde : pcdm.entries()) {
+            ClassInfo clientInfo =
+                    pcdm.getClassInfoForPCDEntry(ClassInfo.VER_OLD, pcde);
+            if (clientInfo == null) {
+                continue;  // New class
+            }
+            String className = clientInfo.name;
+            if (className.equals(declaringClassName)) {
+                continue;
+            }
+            if (!memberAccessibleFrom(declaringClassInfo, memberNo, clientInfo, isField)) {
+                continue;
+            }
+            if (fromDiffPackages &&
+                    declaringClassPackage.equals(clientInfo.packageName)) {
+                continue;
+            }
+            if (onlySubclasses && !clientInfo.isSubclassOf(declaringClassName, false)) {
+                continue;
+            }
+
+            if (isField) {
+                if (clientInfo.referencesField(declaringClassInfo, memberNo)) {
+                    addToAffectedClassNames(clientInfo.name);
+                }
+            } else {
+                if (clientInfo.referencesMethod(declaringClassInfo, memberNo)) {
+                    addToAffectedClassNames(clientInfo.name);
+                }
+            }
+        }
+    }
+
+    /** Checks if class classInfo is accessible from class clientClassInfo. */
+    private boolean classAccessibleFrom(ClassInfo classInfo, ClassInfo clientClassInfo) {
+        char classFlags = classInfo.accessFlags;
+        String classPackage = classInfo.packageName;
+        String clientClassPackage = clientClassInfo.packageName;
+
+        if (Modifier.isPublic(classFlags)) {
+            return true;
+        } else if (Modifier.isProtected(classFlags)) {
+            if (classPackage.equals(clientClassPackage) ||
+                    clientClassInfo.isSubclassOf(classInfo.directlyEnclosingClass, false)) {
+                return true;
+            }
+        } else if (Modifier.isPrivate(classFlags)) {
+            if (classInfo.topLevelEnclosingClass.equals(clientClassInfo.topLevelEnclosingClass)) {
+                return true;
+            }
+        } else {
+            if (classPackage.equals(clientClassPackage)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Checks if member memberNo (which is a field if isField == true, and method otherwise) of class memberClassInfo is
+     * accessible from class clientClassInfo.
+     */
+    private boolean memberAccessibleFrom(ClassInfo memberClassInfo,
+            int memberNo, ClassInfo clientClassInfo, boolean isField) {
+        char memberClassFlags = memberClassInfo.accessFlags;
+        char memberFlags = isField ? memberClassInfo.fieldAccessFlags[memberNo]
+                : memberClassInfo.methodAccessFlags[memberNo];
+        String memberClassPackage = memberClassInfo.packageName;
+        String clientClassPackage = clientClassInfo.packageName;
+
+        if (Modifier.isPublic(memberClassFlags)) {
+            if (Modifier.isPublic(memberFlags)) {
+                return true;
+            } else if (Modifier.isProtected(memberFlags) &&
+                    (memberClassPackage.equals(clientClassPackage) ||
+                    clientClassInfo.isSubclassOf(memberClassInfo.name, false))) {
+                return true;
+            } else if (Modifier.isPrivate(memberFlags)) {
+                if (memberClassInfo.topLevelEnclosingClass.equals(
+                        clientClassInfo.topLevelEnclosingClass)) {
+                    return true;
+                }
+            } else if (memberClassPackage.equals(clientClassPackage)) {
+                return true;
+            }
+        } else if (Modifier.isProtected(memberClassFlags)) {
+            if (!(memberClassPackage.equals(clientClassPackage) ||
+                    clientClassInfo.isSubclassOf(memberClassInfo.directlyEnclosingClass, false))) {
+                return true;
+            }
+            if (Modifier.isPublic(memberFlags) ||
+                    Modifier.isProtected(memberFlags)) {
+                return true;
+            } else if (Modifier.isPrivate(memberFlags)) {
+                if (memberClassInfo.topLevelEnclosingClass.equals(
+                        clientClassInfo.topLevelEnclosingClass)) {
+                    return true;
+                }
+            } else {
+                if (memberClassPackage.equals(clientClassPackage)) {
+                    return true;
+                }
+            }
+        } else if (Modifier.isPrivate(memberClassFlags)) {
+            if (memberClassInfo.topLevelEnclosingClass.equals(
+                    clientClassInfo.topLevelEnclosingClass)) {
+                return true;
+            }
+        } else {  // memberClassInfo is package-private
+            if (!memberClassPackage.equals(clientClassPackage)) {
+                return false;
+            }
+            if (Modifier.isPublic(memberFlags) || Modifier.isProtected(memberFlags)) {
+                return true;
+            } else if (Modifier.isPrivate(memberFlags)) {
+                if (memberClassInfo.topLevelEnclosingClass.equals(
+                        clientClassInfo.topLevelEnclosingClass)) {
+                    return true;
+                }
+            } else {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}