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package com.sun.xml.internal.ws.policy;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.Set;
import java.util.TreeSet;
import javax.xml.namespace.QName;
import com.sun.xml.internal.ws.policy.privateutil.LocalizationMessages;
import com.sun.xml.internal.ws.policy.privateutil.PolicyUtils;
import java.util.LinkedList;
import java.util.List;
/**
* The AssertionSet is a set of assertions. It represents a single policy alternative.
*
* @author Fabian Ritzmann, Marek Potociar
*/
public final class AssertionSet implements Iterable<PolicyAssertion>, Comparable<AssertionSet> {
private static final AssertionSet EMPTY_ASSERTION_SET = new AssertionSet(Collections.unmodifiableList(new LinkedList<PolicyAssertion>()));
/**
* The comparator comapres policy assertions according to their publicly accessible attributes, in the following
* order of attributes:
*
* 1. namespace (not null String)
* 2. local name (not null String)
* 3. value (String): null < "" < "not empty"
* 4. has nested assertions (boolean): false < true
* 5. has nested policy (boolean): false < true
* 6. hashCode comparison
*/
private static final Comparator<PolicyAssertion> ASSERTION_COMPARATOR = new Comparator<PolicyAssertion>() {
public int compare(final PolicyAssertion pa1, final PolicyAssertion pa2) {
if (pa1.equals(pa2)) {
return 0;
}
int result;
result = PolicyUtils.Comparison.QNAME_COMPARATOR.compare(pa1.getName(), pa2.getName());
if (result != 0) {
return result;
}
result = PolicyUtils.Comparison.compareNullableStrings(pa1.getValue(), pa2.getValue());
if (result != 0) {
return result;
}
result = PolicyUtils.Comparison.compareBoolean(pa1.hasNestedAssertions(), pa2.hasNestedAssertions());
if (result != 0) {
return result;
}
result = PolicyUtils.Comparison.compareBoolean(pa1.hasNestedPolicy(), pa2.hasNestedPolicy());
if (result != 0) {
return result;
}
return Math.round(Math.signum(pa1.hashCode() - pa2.hashCode()));
}
};
private final List<PolicyAssertion> assertions;
private final Set<QName> vocabulary = new TreeSet<QName>(PolicyUtils.Comparison.QNAME_COMPARATOR);
private final Collection<QName> immutableVocabulary = Collections.unmodifiableCollection(vocabulary);
private AssertionSet(List<PolicyAssertion> list) {
assert (list != null) : LocalizationMessages.WSP_0037_PRIVATE_CONSTRUCTOR_DOES_NOT_TAKE_NULL();
this.assertions = list;
}
private AssertionSet(final Collection<AssertionSet> alternatives) {
this.assertions = new LinkedList<PolicyAssertion>();
for (AssertionSet alternative : alternatives) {
addAll(alternative.assertions);
}
}
private boolean add(final PolicyAssertion assertion) {
if (assertion == null) {
return false;
}
if (this.assertions.contains(assertion)) {
return false;
} else {
this.assertions.add(assertion);
this.vocabulary.add(assertion.getName());
return true;
}
}
private boolean addAll(final Collection<? extends PolicyAssertion> assertions) {
boolean result = true;
if (assertions != null) {
for (PolicyAssertion assertion : assertions) {
result &= add(assertion); // this is here to ensure that vocabulary is built correctly as well
}
}
return result;
}
/**
* Return all assertions contained in this assertion set.
*
* @return All assertions contained in this assertion set
*/
Collection<PolicyAssertion> getAssertions() {
return assertions;
}
/**
* Retrieves the vocabulary of this policy expression. The vocabulary is represented by an immutable collection of
* unique QName objects. Each of those objects represents single assertion type contained in the assertion set.
*
* @return immutable collection of assertion types contained in the assertion set (a policy vocabulary).
*/
Collection<QName> getVocabulary() {
return immutableVocabulary;
}
/**
* Checks whether this policy alternative is compatible with the provided policy alternative.
*
* @param alternative policy alternative used for compatibility test
* @param mode compatibility mode to be used
* @return {@code true} if the two policy alternatives are compatible, {@code false} otherwise
*/
boolean isCompatibleWith(final AssertionSet alternative, PolicyIntersector.CompatibilityMode mode) {
boolean result = (mode == PolicyIntersector.CompatibilityMode.LAX) || this.vocabulary.equals(alternative.vocabulary);
result = result && this.areAssertionsCompatible(alternative, mode);
result = result && alternative.areAssertionsCompatible(this, mode);
return result;
}
private boolean areAssertionsCompatible(final AssertionSet alternative, PolicyIntersector.CompatibilityMode mode) {
nextAssertion: for (PolicyAssertion thisAssertion : this.assertions) {
if ((mode == PolicyIntersector.CompatibilityMode.STRICT) || !thisAssertion.isIgnorable()) {
for (PolicyAssertion thatAssertion : alternative.assertions) {
if (thisAssertion.isCompatibleWith(thatAssertion, mode)) {
continue nextAssertion;
}
}
return false;
}
}
return true;
}
/**
* Creates and returns new assertion set holding content of all provided policy assertion sets.
* <p/>
* This method should not be used to perform a merge of general Policy instances. A client should be aware of the
* method's result meaning and the difference between merge of Policy instances and merge of AssertionSet instances.
*
*
* @param alternatives collection of provided policy assertion sets which content is to be stored in the assertion set.
* May be {@code null} - empty assertion set is returned in such case.
* @return new instance of assertion set holding the content of all provided policy assertion sets.
*/
public static AssertionSet createMergedAssertionSet(final Collection<AssertionSet> alternatives) {
if (alternatives == null || alternatives.isEmpty()) {
return EMPTY_ASSERTION_SET;
}
final AssertionSet result = new AssertionSet(alternatives);
Collections.sort(result.assertions, ASSERTION_COMPARATOR);
return result;
}
/**
* Creates and returns new assertion set holding a set of provided policy assertions.
*
* @param assertions collection of provided policy assertions to be stored in the assertion set. May be {@code null}.
* @return new instance of assertion set holding the provided policy assertions
*/
public static AssertionSet createAssertionSet(final Collection<? extends PolicyAssertion> assertions) {
if (assertions == null || assertions.isEmpty()) {
return EMPTY_ASSERTION_SET;
}
final AssertionSet result = new AssertionSet(new LinkedList<PolicyAssertion>());
result.addAll(assertions);
Collections.sort(result.assertions, ASSERTION_COMPARATOR);
return result;
}
public static AssertionSet emptyAssertionSet() {
return EMPTY_ASSERTION_SET;
}
/**
* Returns an iterator over a set of child policy assertion objects.
*
* @return policy assertion Iterator.
*/
public Iterator<PolicyAssertion> iterator() {
return this.assertions.iterator();
}
/**
* Searches for assertions with given name. Only assertions that are contained as immediate children of the assertion set are
* searched, i.e. nested policies are not searched.
*
* @param name The fully qualified name of searched assertion
* @return List of all assertions matching the requested name. If no assertions are found, the returned list is empty
* (i.e. {@code null} value is never returned).
*/
public Collection<PolicyAssertion> get(final QName name) {
final List<PolicyAssertion> matched = new LinkedList<PolicyAssertion>();
if (vocabulary.contains(name)) {
// we iterate the assertion set only if we are sure we contain such assertion name in our vocabulary
for (PolicyAssertion assertion : assertions) {
if (assertion.getName().equals(name)) {
matched.add(assertion);
}
}
}
return matched;
}
/**
* Returns {@code true} if this assertion set contains no assertions.
*
* @return {@code true} if this assertion set contains no assertions.
*/
public boolean isEmpty() {
return assertions.isEmpty();
}
/**
* Returns true if the assertion set contains the assertion name specified in its vocabulary
*
* @param assertionName the fully qualified name of the assertion
* @return {@code true}, if an assertion with the given name could be found in the assertion set vocabulary {@code false} otherwise.
*/
public boolean contains(final QName assertionName) {
return vocabulary.contains(assertionName);
}
/**
* An {@code Comparable<T>.compareTo(T o)} interface method implementation.
* @param that other alternative to compare with
*/
public int compareTo(final AssertionSet that) {
if (this.equals(that)) {
return 0;
}
// comparing vocabularies
final Iterator<QName> vIterator1 = this.getVocabulary().iterator();
final Iterator<QName> vIterator2 = that.getVocabulary().iterator();
while (vIterator1.hasNext()) {
final QName entry1 = vIterator1.next();
if (vIterator2.hasNext()) {
final QName entry2 = vIterator2.next();
final int result = PolicyUtils.Comparison.QNAME_COMPARATOR.compare(entry1, entry2);
if (result != 0) {
return result;
}
} else {
return 1; // we have more entries in this vocabulary
}
}
if (vIterator2.hasNext()) {
return -1; // we have more entries in that vocabulary
}
// vocabularies are equal => comparing assertions
final Iterator<PolicyAssertion> pIterator1 = this.getAssertions().iterator();
final Iterator<PolicyAssertion> pIterator2 = that.getAssertions().iterator();
while (pIterator1.hasNext()) {
final PolicyAssertion pa1 = pIterator1.next();
if (pIterator2.hasNext()) {
final PolicyAssertion pa2 = pIterator2.next();
final int result = ASSERTION_COMPARATOR.compare(pa1, pa2);
if (result != 0) {
return result;
}
} else {
return 1; // we have more entries in this assertion set
}
}
if (pIterator2.hasNext()) {
return -1; // we have more entries in that assertion set
}
// seems like objects are very simmilar although not equal => we must not return 0 otherwise the TreeSet
// holding this element would discard the newly added element. Thus we return that the first argument is
// greater than second (just because it is first...)
return 1;
}
/**
* An {@code Object.equals(Object obj)} method override.
*/
public boolean equals(final Object obj) {
if (this == obj) {
return true;
}
if (!(obj instanceof AssertionSet)) {
return false;
}
final AssertionSet that = (AssertionSet) obj;
boolean result = true;
result = result && this.vocabulary.equals(that.vocabulary);
result = result && this.assertions.size() == that.assertions.size() && this.assertions.containsAll(that.assertions);
return result;
}
/**
* An {@code Object.hashCode()} method override.
*/
public int hashCode() {
int result = 17;
result = 37 * result + vocabulary.hashCode();
result = 37 * result + assertions.hashCode();
return result;
}
/**
* An {@code Object.toString()} method override.
*/
public String toString() {
return toString(0, new StringBuffer()).toString();
}
/**
* A helper method that appends indented string representation of this instance to the input string buffer.
*
* @param indentLevel indentation level to be used.
* @param buffer buffer to be used for appending string representation of this instance
* @return modified buffer containing new string representation of the instance
*/
StringBuffer toString(final int indentLevel, final StringBuffer buffer) {
final String indent = PolicyUtils.Text.createIndent(indentLevel);
final String innerIndent = PolicyUtils.Text.createIndent(indentLevel + 1);
buffer.append(indent).append("assertion set {").append(PolicyUtils.Text.NEW_LINE);
if (assertions.isEmpty()) {
buffer.append(innerIndent).append("no assertions").append(PolicyUtils.Text.NEW_LINE);
} else {
for (PolicyAssertion assertion : assertions) {
assertion.toString(indentLevel + 1, buffer).append(PolicyUtils.Text.NEW_LINE);
}
}
buffer.append(indent).append('}');
return buffer;
}
}