/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at legal-notices/CDDLv1_0.txt
* or http://forgerock.org/license/CDDLv1.0.html.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at legal-notices/CDDLv1_0.txt.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information:
* Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*
*
* Copyright 2010 Sun Microsystems, Inc.
* Portions copyright 2012 ForgeRock AS.
*/
package org.forgerock.opendj.ldap.controls;
import static com.forgerock.opendj.util.StaticUtils.byteToHex;
import static com.forgerock.opendj.util.StaticUtils.getExceptionMessage;
import static com.forgerock.opendj.ldap.CoreMessages.ERR_VLVREQ_CONTROL_BAD_OID;
import static com.forgerock.opendj.ldap.CoreMessages.INFO_VLVREQ_CONTROL_CANNOT_DECODE_VALUE;
import static com.forgerock.opendj.ldap.CoreMessages.INFO_VLVREQ_CONTROL_INVALID_TARGET_TYPE;
import static com.forgerock.opendj.ldap.CoreMessages.INFO_VLVREQ_CONTROL_NO_VALUE;
import java.io.IOException;
import org.forgerock.i18n.LocalizableMessage;
import org.forgerock.opendj.asn1.ASN1;
import org.forgerock.opendj.asn1.ASN1Reader;
import org.forgerock.opendj.asn1.ASN1Writer;
import org.forgerock.opendj.ldap.ByteString;
import org.forgerock.opendj.ldap.ByteStringBuilder;
import org.forgerock.opendj.ldap.DecodeException;
import org.forgerock.opendj.ldap.DecodeOptions;
import com.forgerock.opendj.util.Validator;
/**
* The virtual list view request control as defined in
* draft-ietf-ldapext-ldapv3-vlv. This control allows a client to specify that
* the server return, for a given search request with associated sort keys, a
* contiguous subset of the search result set. This subset is specified in terms
* of offsets into the ordered list, or in terms of a greater than or equal
* assertion value.
*
* This control must be used in conjunction with the server-side sort request
* control in order to ensure that results are returned in a consistent order.
*
* This control is similar to the simple paged results request control, except
* that it allows the client to move backwards and forwards in the result set.
*
* The following example demonstrates use of the virtual list view controls.
*
*
* ByteString contextID = ByteString.empty();
*
* // Add a window of 2 entries on either side of the first sn=Jensen entry.
* SearchRequest request = Requests.newSearchRequest("ou=People,dc=example,dc=com",
* SearchScope.WHOLE_SUBTREE, "(sn=*)", "sn", "givenName")
* .addControl(ServerSideSortRequestControl.newControl(true, new SortKey("sn")))
* .addControl(VirtualListViewRequestControl.newAssertionControl(
* true, ByteString.valueOf("Jensen"), 2, 2, contextID));
*
* SearchResultHandler resultHandler = new MySearchResultHandler();
* Result result = connection.search(request, resultHandler);
*
* ServerSideSortResponseControl sssControl =
* result.getControl(ServerSideSortResponseControl.DECODER, new DecodeOptions());
* if (sssControl != null && sssControl.getResult() == ResultCode.SUCCESS) {
* // Entries are sorted.
* } else {
* // Entries not necessarily sorted
* }
*
* VirtualListViewResponseControl vlvControl =
* result.getControl(VirtualListViewResponseControl.DECODER, new DecodeOptions());
* // Position in list: vlvControl.getTargetPosition()/vlvControl.getContentCount()
*
*
* The search result handler in this case displays pages of results as LDIF on
* standard out.
*
*
* private static class MySearchResultHandler implements SearchResultHandler {
*
* {@literal @}Override
* public void handleErrorResult(ErrorResultException error) {
* // Ignore.
* }
*
* {@literal @}Override
* public void handleResult(Result result) {
* // Ignore.
* }
*
* {@literal @}Override
* public boolean handleEntry(SearchResultEntry entry) {
* final LDIFEntryWriter writer = new LDIFEntryWriter(System.out);
* try {
* writer.writeEntry(entry);
* writer.flush();
* } catch (final IOException e) {
* // The writer could not write to System.out.
* }
* return true;
* }
*
* {@literal @}Override
* public boolean handleReference(SearchResultReference reference) {
* System.out.println("Got a reference: " + reference.toString());
* return false;
* }
* }
*
*
* @see VirtualListViewResponseControl
* @see ServerSideSortRequestControl
* @see
* draft-ietf-ldapext-ldapv3-vlv - LDAP Extensions for Scrolling View
* Browsing of Search Results
*/
public final class VirtualListViewRequestControl implements Control {
/**
* The OID for the virtual list view request control.
*/
public static final String OID = "2.16.840.1.113730.3.4.9";
/**
* A decoder which can be used for decoding the virtual list view request
* control.
*/
public static final ControlDecoder DECODER =
new ControlDecoder() {
public VirtualListViewRequestControl decodeControl(final Control control,
final DecodeOptions options) throws DecodeException {
Validator.ensureNotNull(control);
if (control instanceof VirtualListViewRequestControl) {
return (VirtualListViewRequestControl) control;
}
if (!control.getOID().equals(OID)) {
final LocalizableMessage message =
ERR_VLVREQ_CONTROL_BAD_OID.get(control.getOID(), OID);
throw DecodeException.error(message);
}
if (!control.hasValue()) {
// The request control must always have a value.
final LocalizableMessage message = INFO_VLVREQ_CONTROL_NO_VALUE.get();
throw DecodeException.error(message);
}
final ASN1Reader reader = ASN1.getReader(control.getValue());
try {
reader.readStartSequence();
final int beforeCount = (int) reader.readInteger();
final int afterCount = (int) reader.readInteger();
int offset = -1;
int contentCount = -1;
ByteString assertionValue = null;
final byte targetType = reader.peekType();
switch (targetType) {
case TYPE_TARGET_BYOFFSET:
reader.readStartSequence();
offset = (int) reader.readInteger();
contentCount = (int) reader.readInteger();
reader.readEndSequence();
break;
case TYPE_TARGET_GREATERTHANOREQUAL:
assertionValue = reader.readOctetString();
break;
default:
final LocalizableMessage message =
INFO_VLVREQ_CONTROL_INVALID_TARGET_TYPE
.get(byteToHex(targetType));
throw DecodeException.error(message);
}
ByteString contextID = null;
if (reader.hasNextElement()) {
contextID = reader.readOctetString();
}
return new VirtualListViewRequestControl(control.isCritical(), beforeCount,
afterCount, contentCount, offset, assertionValue, contextID);
} catch (final IOException e) {
final LocalizableMessage message =
INFO_VLVREQ_CONTROL_CANNOT_DECODE_VALUE.get(getExceptionMessage(e));
throw DecodeException.error(message, e);
}
}
public String getOID() {
return OID;
}
};
/**
* The BER type to use when encoding the byOffset target element.
*/
private static final byte TYPE_TARGET_BYOFFSET = (byte) 0xA0;
/**
* The BER type to use when encoding the greaterThanOrEqual target element.
*/
private static final byte TYPE_TARGET_GREATERTHANOREQUAL = (byte) 0x81;
/**
* Creates a new virtual list view request control that will identify the
* target entry by an assertion value. The assertion value is encoded
* according to the ORDERING matching rule for the attribute description in
* the sort control. The assertion value is used to determine the target
* entry by comparison with the values of the attribute specified as the
* primary sort key. The first list entry who's value is no less than (less
* than or equal to when the sort order is reversed) the supplied value is
* the target entry.
*
* @param isCritical
* {@code true} if it is unacceptable to perform the operation
* without applying the semantics of this control, or
* {@code false} if it can be ignored.
* @param assertionValue
* The assertion value that will be used to locate the target
* entry.
* @param beforeCount
* The number of entries before the target entry to be included
* in the search results.
* @param afterCount
* The number of entries after the target entry to be included in
* the search results.
* @param contextID
* The context ID provided by the server in the last virtual list
* view response for the same set of criteria, or {@code null} if
* there was no previous virtual list view response or the server
* did not include a context ID in the last response.
* @return The new control.
* @throws IllegalArgumentException
* If {@code beforeCount} or {@code afterCount} were less than
* {@code 0}.
* @throws NullPointerException
* If {@code assertionValue} was {@code null}.
*/
public static VirtualListViewRequestControl newAssertionControl(final boolean isCritical,
final ByteString assertionValue, final int beforeCount, final int afterCount,
final ByteString contextID) {
Validator.ensureNotNull(assertionValue);
Validator.ensureTrue(beforeCount >= 0, "beforeCount is less than 0");
Validator.ensureTrue(afterCount >= 0, "afterCount is less than 0");
return new VirtualListViewRequestControl(isCritical, beforeCount, afterCount, -1, -1,
assertionValue, contextID);
}
/**
* Creates a new virtual list view request control that will identify the
* target entry by a positional offset within the complete result set.
*
* @param isCritical
* {@code true} if it is unacceptable to perform the operation
* without applying the semantics of this control, or
* {@code false} if it can be ignored.
* @param offset
* The positional offset of the target entry in the result set,
* where {@code 1} is the first entry.
* @param contentCount
* The content count returned by the server in the last virtual
* list view response, or {@code 0} if this is the first virtual
* list view request.
* @param beforeCount
* The number of entries before the target entry to be included
* in the search results.
* @param afterCount
* The number of entries after the target entry to be included in
* the search results.
* @param contextID
* The context ID provided by the server in the last virtual list
* view response for the same set of criteria, or {@code null} if
* there was no previous virtual list view response or the server
* did not include a context ID in the last response.
* @return The new control.
* @throws IllegalArgumentException
* If {@code beforeCount}, {@code afterCount}, or
* {@code contentCount} were less than {@code 0}, or if
* {@code offset} was less than {@code 1}.
*/
public static VirtualListViewRequestControl newOffsetControl(final boolean isCritical,
final int offset, final int contentCount, final int beforeCount, final int afterCount,
final ByteString contextID) {
Validator.ensureTrue(beforeCount >= 0, "beforeCount is less than 0");
Validator.ensureTrue(afterCount >= 0, "afterCount is less than 0");
Validator.ensureTrue(offset > 0, "beforeCount is less than 1");
Validator.ensureTrue(contentCount >= 0, "afterCount is less than 0");
return new VirtualListViewRequestControl(isCritical, beforeCount, afterCount, offset,
contentCount, null, contextID);
}
private final int beforeCount;
private final int afterCount;
private final ByteString contextID;
private final boolean isCritical;
private final int contentCount;
private final int offset;
private final ByteString assertionValue;
private VirtualListViewRequestControl(final boolean isCritical, final int beforeCount,
final int afterCount, final int contentCount, final int offset,
final ByteString assertionValue, final ByteString contextID) {
this.isCritical = isCritical;
this.beforeCount = beforeCount;
this.afterCount = afterCount;
this.contentCount = contentCount;
this.offset = offset;
this.assertionValue = assertionValue;
this.contextID = contextID;
}
/**
* Returns the number of entries after the target entry to be included in
* the search results.
*
* @return The number of entries after the target entry to be included in
* the search results.
*/
public int getAfterCount() {
return afterCount;
}
/**
* Returns the assertion value that will be used to locate the target entry,
* if applicable.
*
* @return The assertion value that will be used to locate the target entry,
* or {@code null} if this control is using a target offset.
*/
public ByteString getAssertionValue() {
return assertionValue;
}
/**
* Returns the assertion value that will be used to locate the target entry,
* if applicable, decoded as a UTF-8 string.
*
* @return The assertion value that will be used to locate the target entry
* decoded as a UTF-8 string, or {@code null} if this control is
* using a target offset.
*/
public String getAssertionValueAsString() {
return assertionValue != null ? assertionValue.toString() : null;
}
/**
* Returns the number of entries before the target entry to be included in
* the search results.
*
* @return The number of entries before the target entry to be included in
* the search results.
*/
public int getBeforeCount() {
return beforeCount;
}
/**
* Returns the content count returned by the server in the last virtual list
* view response, if applicable.
*
* @return The content count returned by the server in the last virtual list
* view response, which may be {@code 0} if this is the first
* virtual list view request, or {@code -1} if this control is using
* a target assertion.
*/
public int getContentCount() {
return contentCount;
}
/**
* Returns the context ID provided by the server in the last virtual list
* view response for the same set of criteria, or {@code null} if there was
* no previous virtual list view response or the server did not include a
* context ID in the last response.
*
* @return The context ID provided by the server in the last virtual list
* view response, or {@code null} if unavailable.
*/
public ByteString getContextID() {
return contextID;
}
/**
* Returns the positional offset of the target entry in the result set, if
* applicable, where {@code 1} is the first entry.
*
* @return The positional offset of the target entry in the result set, or
* {@code -1} if this control is using a target assertion.
*/
public int getOffset() {
return offset;
}
/**
* {@inheritDoc}
*/
public String getOID() {
return OID;
}
/**
* {@inheritDoc}
*/
public ByteString getValue() {
final ByteStringBuilder buffer = new ByteStringBuilder();
final ASN1Writer writer = ASN1.getWriter(buffer);
try {
writer.writeStartSequence();
writer.writeInteger(beforeCount);
writer.writeInteger(afterCount);
if (hasTargetOffset()) {
writer.writeStartSequence(TYPE_TARGET_BYOFFSET);
writer.writeInteger(offset);
writer.writeInteger(contentCount);
writer.writeEndSequence();
} else {
writer.writeOctetString(TYPE_TARGET_GREATERTHANOREQUAL, assertionValue);
}
if (contextID != null) {
writer.writeOctetString(contextID);
}
writer.writeEndSequence();
return buffer.toByteString();
} catch (final IOException ioe) {
// This should never happen unless there is a bug somewhere.
throw new RuntimeException(ioe);
}
}
/**
* Returns {@code true} if this control is using a target offset, or
* {@code false} if this control is using a target assertion.
*
* @return {@code true} if this control is using a target offset, or
* {@code false} if this control is using a target assertion.
*/
public boolean hasTargetOffset() {
return assertionValue != null ? false : true;
}
/**
* {@inheritDoc}
*/
public boolean hasValue() {
return true;
}
/**
* {@inheritDoc}
*/
public boolean isCritical() {
return isCritical;
}
/**
* {@inheritDoc}
*/
@Override
public String toString() {
final StringBuilder builder = new StringBuilder();
builder.append("VirtualListViewRequestControl(oid=");
builder.append(getOID());
builder.append(", criticality=");
builder.append(isCritical());
builder.append(", beforeCount=");
builder.append(beforeCount);
builder.append(", afterCount=");
builder.append(afterCount);
if (hasTargetOffset()) {
builder.append(", offset=");
builder.append(offset);
builder.append(", contentCount=");
builder.append(contentCount);
} else {
builder.append(", greaterThanOrEqual=");
builder.append(assertionValue);
}
if (contextID != null) {
builder.append(", contextID=");
builder.append(contextID);
}
builder.append(")");
return builder.toString();
}
}