The Java Tutorials have been written for JDK 8.Java教程是为JDK 8编写的。Examples and practices described in this page don't take advantage of improvements introduced in later releases and might use technology no longer available.本页中描述的示例和实践没有利用后续版本中引入的改进，并且可能使用不再可用的技术。See Java Language Changes for a summary of updated language features in Java SE 9 and subsequent releases.有关Java SE 9及其后续版本中更新的语言特性的摘要，请参阅Java语言更改。
See JDK Release Notes for information about new features, enhancements, and removed or deprecated options for all JDK releases.有关所有JDK版本的新功能、增强功能以及已删除或不推荐的选项的信息，请参阅JDK发行说明。
To read the attributes of an object from the directory, use DirContext.getAttributes() and pass it the name of the object for which you want the attributes. Suppose that an object in the naming service has the name "cn=Ted Geisel, ou=People". To retrieve this object's attributes, you'll need code that looks like this:
Attributes answer = ctx.getAttributes("cn=Ted Geisel, ou=People");You can then print the contents of this answer as follows.
for (NamingEnumeration ae = answer.getAll(); ae.hasMore();) {
Attribute attr = (Attribute)ae.next();
System.out.println("attribute: " + attr.getID());
/* Print each value */
for (NamingEnumeration e = attr.getAll(); e.hasMore();
System.out.println("value: " + e.next()))
;
}This produces the following output.
# java GetattrsAll attribute: sn value: Geisel attribute: objectclass value: top value: person value: organizationalPerson value: inetOrgPerson attribute: jpegphoto value: [B@1dacd78b attribute: mail value: Ted.Geisel@JNDITutorial.example.com attribute: facsimiletelephonenumber value: +1 408 555 2329 attribute: telephonenumber value: +1 408 555 5252 attribute: cn value: Ted Geisel
To read a selective subset of attributes, you supply an array of strings that are attribute identifiers of the attributes that you want to retrieve.
// Specify the ids of the attributes to return
String[] attrIDs = {"sn", "telephonenumber", "golfhandicap", "mail"};
// Get the attributes requested
Attributes answer = ctx.getAttributes("cn=Ted Geisel, ou=People", attrIDs);This example asks for the "sn", "telephonenumber", "golfhandicap" and "mail" attributes of the object "cn=Ted Geisel, ou=People". This object has all but the "golfhandicap" attribute, and so three attributes are returned in the answer. Following is the output of the example.
# java Getattrs attribute: sn value: Geisel attribute: mail value: Ted.Geisel@JNDITutorial.example.com attribute: telephonenumber value: +1 408 555 5252