package org.apache.shiro.web.faces.tags;
import org.apache.shiro.subject.PrincipalCollection;
import javax.faces.context.FacesContext;
import java.beans.BeanInfo;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.io.IOException;
import java.lang.reflect.Modifier;
/**
* <p>Tag used to print out the String value of a user's default principal,
* or a specific principal as specified by the tag's attributes.</p>
* <p/>
* <p> If no attributes are specified, the tag prints out the <tt>toString()</tt>
* value of the user's default principal. If the <tt>type</tt> attribute
* is specified, the tag looks for a principal with the given type. If the
* <tt>property</tt> attribute is specified, the tag prints the string value of
* the specified property of the principal. If no principal is found or the user
* is not authenticated, the tag displays nothing unless a <tt>defaultValue</tt>
* is specified.</p>
*
* @author Jeremy Haile
* @author Deluan Quintao
*/
public class PrincipalTag extends SecureComponent {
/**
* The type of principal to be retrieved, or null if the default principal should be used.
*/
private String type;
/**
* The property name to retrieve of the principal, or null if the <tt>toString()</tt> value should be used.
*/
private String property;
/**
* The default value that should be displayed if the user is not authenticated, or no principal is found.
*/
private String defaultValue;
/*--------------------------------------------
| A C C E S S O R S / M O D I F I E R S |
============================================*/
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
public String getProperty() {
return property;
}
public void setProperty(String property) {
this.property = property;
}
public String getDefaultValue() {
return defaultValue;
}
public void setDefaultValue(String defaultValue) {
this.defaultValue = defaultValue;
}
/*--------------------------------------------
| M E T H O D S |
============================================*/
@SuppressWarnings({"unchecked"})
protected void doEncodeAll(FacesContext ctx) throws IOException {
String strValue = null;
try {
if (getSubject() != null) {
// Get the principal to print out
Object principal;
if (type == null) {
principal = getSubject().getPrincipal();
} else {
principal = getPrincipalFromClassName();
}
// Get the string value of the principal
if (principal != null) {
if (property == null) {
strValue = principal.toString();
} else {
strValue = getPrincipalProperty(principal, property);
}
}
}
} catch (Exception e) {
log.error("Error getting principal type [" + type + "], property [" + property + "]: " + e.getMessage(), e);
}
if (strValue == null) {
strValue = defaultValue;
}
// Print out the principal value if not null
if (strValue != null) {
try {
ctx.getResponseWriter().write(strValue);
} catch (IOException e) {
throw new IOException("Error writing [" + strValue + "] to output.");
}
}
}
@SuppressWarnings({"unchecked"})
private Object getPrincipalFromClassName() {
Object principal = null;
try {
Class cls = Class.forName(type);
PrincipalCollection principals = getSubject().getPrincipals();
if (principals != null) {
principal = principals.oneByType(cls);
}
} catch (ClassNotFoundException e) {
if (log.isErrorEnabled()) {
log.error("Unable to find class for name [" + type + "]");
}
} catch (Exception e) {
if (log.isErrorEnabled()) {
log.error("Unknown error while getting principal for type [" + type + "]: " + e.getMessage(), e);
}
}
return principal;
}
private String getPrincipalProperty(Object principal, String property) throws IOException {
String strValue = null;
try {
BeanInfo bi = Introspector.getBeanInfo(principal.getClass());
// Loop through the properties to get the string value of the specified property
boolean foundProperty = false;
for (PropertyDescriptor pd : bi.getPropertyDescriptors()) {
if (pd.getName().equals(property) && (Modifier.isPublic(pd.getReadMethod().getModifiers()))) {
Object value = null;
try {
pd.getReadMethod().setAccessible(true);
value = pd.getReadMethod().invoke(principal, (Object[]) null);
} finally {
pd.getReadMethod().setAccessible(false);
}
strValue = String.valueOf(value);
foundProperty = true;
break;
}
}
if (!foundProperty) {
final String message = "Property [" + property + "] not found in principal of type [" + principal.getClass().getName() + "]";
if (log.isErrorEnabled()) {
log.error(message);
}
throw new IOException(message);
}
} catch (Exception e) {
final String message = "Error reading property [" + property + "] from principal of type [" + principal.getClass().getName() + "]";
if (log.isErrorEnabled()) {
log.error(message, e);
}
throw new IOException(message);
}
return strValue;
}
// ----------------------------------------------------- StateHolder Methods
private Object[] values;
@Override
public Object saveState(FacesContext context) {
if (values == null) {
values = new Object[4];
}
values[0] = super.saveState(context);
values[1] = type;
values[2] = property;
values[3] = defaultValue;
return values;
}
@Override
public void restoreState(FacesContext context, Object state) {
values = (Object[]) state;
super.restoreState(context, values[0]);
type = (String) values[1];
property = (String) values[2];
defaultValue = (String) values[3];
}
}