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* published by the Free Software Foundation. Oracle designates this
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*
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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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* 2 along with this work; if not, write to the Free Software Foundation,
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*
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package javax.naming.ldap;
import java.io.IOException;
import com.sun.jndi.ldap.Ber;
import com.sun.jndi.ldap.BerEncoder;
Requests that the results of a search operation be returned by the LDAP
server in batches of a specified size.
The requestor controls the rate at which batches are returned by the rate
at which it invokes search operations.
The following code sample shows how the class may be used:
// Open an LDAP association
LdapContext ctx = new InitialLdapContext();
// Activate paged results
int pageSize = 20; // 20 entries per page
byte[] cookie = null;
int total;
ctx.setRequestControls(new Control[]{
new PagedResultsControl(pageSize, Control.CRITICAL) });
do {
// Perform the search
NamingEnumeration results =
ctx.search("", "(objectclass=*)", new SearchControls());
// Iterate over a batch of search results
while (results != null && results.hasMore()) {
// Display an entry
SearchResult entry = (SearchResult)results.next();
System.out.println(entry.getName());
System.out.println(entry.getAttributes());
// Handle the entry's response controls (if any)
if (entry instanceof HasControls) {
// ((HasControls)entry).getControls();
}
}
// Examine the paged results control response
Control[] controls = ctx.getResponseControls();
if (controls != null) {
for (int i = 0; i < controls.length; i++) {
if (controls[i] instanceof PagedResultsResponseControl) {
PagedResultsResponseControl prrc =
(PagedResultsResponseControl)controls[i];
total = prrc.getResultSize();
cookie = prrc.getCookie();
} else {
// Handle other response controls (if any)
}
}
}
// Re-activate paged results
ctx.setRequestControls(new Control[]{
new PagedResultsControl(pageSize, cookie, Control.CRITICAL) });
} while (cookie != null);
// Close the LDAP association
ctx.close();
...
This class implements the LDAPv3 Control for paged-results as defined in
RFC 2696.
The control's value has the following ASN.1 definition:
realSearchControlValue ::= SEQUENCE {
size INTEGER (0..maxInt),
-- requested page size from client
-- result set size estimate from server
cookie OCTET STRING
}
Author: Vincent Ryan See Also: Since: 1.5
/**
* Requests that the results of a search operation be returned by the LDAP
* server in batches of a specified size.
* The requestor controls the rate at which batches are returned by the rate
* at which it invokes search operations.
* <p>
* The following code sample shows how the class may be used:
* <pre>{@code
*
* // Open an LDAP association
* LdapContext ctx = new InitialLdapContext();
*
* // Activate paged results
* int pageSize = 20; // 20 entries per page
* byte[] cookie = null;
* int total;
* ctx.setRequestControls(new Control[]{
* new PagedResultsControl(pageSize, Control.CRITICAL) });
*
* do {
* // Perform the search
* NamingEnumeration results =
* ctx.search("", "(objectclass=*)", new SearchControls());
*
* // Iterate over a batch of search results
* while (results != null && results.hasMore()) {
* // Display an entry
* SearchResult entry = (SearchResult)results.next();
* System.out.println(entry.getName());
* System.out.println(entry.getAttributes());
*
* // Handle the entry's response controls (if any)
* if (entry instanceof HasControls) {
* // ((HasControls)entry).getControls();
* }
* }
* // Examine the paged results control response
* Control[] controls = ctx.getResponseControls();
* if (controls != null) {
* for (int i = 0; i < controls.length; i++) {
* if (controls[i] instanceof PagedResultsResponseControl) {
* PagedResultsResponseControl prrc =
* (PagedResultsResponseControl)controls[i];
* total = prrc.getResultSize();
* cookie = prrc.getCookie();
* } else {
* // Handle other response controls (if any)
* }
* }
* }
*
* // Re-activate paged results
* ctx.setRequestControls(new Control[]{
* new PagedResultsControl(pageSize, cookie, Control.CRITICAL) });
* } while (cookie != null);
*
* // Close the LDAP association
* ctx.close();
* ...
*
* } </pre>
* <p>
* This class implements the LDAPv3 Control for paged-results as defined in
* <a href="http://www.ietf.org/rfc/rfc2696.txt">RFC 2696</a>.
*
* The control's value has the following ASN.1 definition:
* <pre>{@code
*
* realSearchControlValue ::= SEQUENCE {
* size INTEGER (0..maxInt),
* -- requested page size from client
* -- result set size estimate from server
* cookie OCTET STRING
* }
*
* }</pre>
*
* @since 1.5
* @see PagedResultsResponseControl
* @author Vincent Ryan
*/
final public class PagedResultsControl extends BasicControl {
The paged-results control's assigned object identifier
is 1.2.840.113556.1.4.319.
/**
* The paged-results control's assigned object identifier
* is 1.2.840.113556.1.4.319.
*/
public static final String OID = "1.2.840.113556.1.4.319";
private static final byte[] EMPTY_COOKIE = new byte[0];
private static final long serialVersionUID = 6684806685736844298L;
Constructs a control to set the number of entries to be returned per
page of results.
Params: - pageSize – The number of entries to return in a page.
- criticality – If true then the server must honor the control
and return search results as indicated by
pageSize or refuse to perform the search.
If false, then the server need not honor the
control.
Throws: - IOException – If an error was encountered while encoding the
supplied arguments into a control.
/**
* Constructs a control to set the number of entries to be returned per
* page of results.
*
* @param pageSize The number of entries to return in a page.
* @param criticality If true then the server must honor the control
* and return search results as indicated by
* pageSize or refuse to perform the search.
* If false, then the server need not honor the
* control.
* @exception IOException If an error was encountered while encoding the
* supplied arguments into a control.
*/
public PagedResultsControl(int pageSize, boolean criticality)
throws IOException {
super(OID, criticality, null);
value = setEncodedValue(pageSize, EMPTY_COOKIE);
}
Constructs a control to set the number of entries to be returned per
page of results. The cookie is provided by the server and may be
obtained from the paged-results response control.
A sequence of paged-results can be abandoned by setting the pageSize
to zero and setting the cookie to the last cookie received from the
server.
Params: - pageSize – The number of entries to return in a page.
- cookie – A possibly null server-generated cookie.
- criticality – If true then the server must honor the control
and return search results as indicated by
pageSize or refuse to perform the search.
If false, then the server need not honor the
control.
Throws: - IOException – If an error was encountered while encoding the
supplied arguments into a control.
/**
* Constructs a control to set the number of entries to be returned per
* page of results. The cookie is provided by the server and may be
* obtained from the paged-results response control.
* <p>
* A sequence of paged-results can be abandoned by setting the pageSize
* to zero and setting the cookie to the last cookie received from the
* server.
*
* @param pageSize The number of entries to return in a page.
* @param cookie A possibly null server-generated cookie.
* @param criticality If true then the server must honor the control
* and return search results as indicated by
* pageSize or refuse to perform the search.
* If false, then the server need not honor the
* control.
* @exception IOException If an error was encountered while encoding the
* supplied arguments into a control.
*/
public PagedResultsControl(int pageSize, byte[] cookie,
boolean criticality) throws IOException {
super(OID, criticality, null);
if (cookie == null) {
cookie = EMPTY_COOKIE;
}
value = setEncodedValue(pageSize, cookie);
}
/*
* Encodes the paged-results control's value using ASN.1 BER.
* The result includes the BER tag and length for the control's value but
* does not include the control's object identifier and criticality setting.
*
* @param pageSize The number of entries to return in a page.
* @param cookie A non-null server-generated cookie.
* @return A possibly null byte array representing the ASN.1 BER encoded
* value of the LDAP paged-results control.
* @exception IOException If a BER encoding error occurs.
*/
private byte[] setEncodedValue(int pageSize, byte[] cookie)
throws IOException {
// build the ASN.1 encoding
BerEncoder ber = new BerEncoder(10 + cookie.length);
ber.beginSeq(Ber.ASN_SEQUENCE | Ber.ASN_CONSTRUCTOR);
ber.encodeInt(pageSize);
ber.encodeOctetString(cookie, Ber.ASN_OCTET_STR);
ber.endSeq();
return ber.getTrimmedBuf();
}
}