package org.codehaus.plexus.component.repository.exception;
   
   import java.io.ByteArrayOutputStream;
   import java.io.PrintStream;
   
   import org.codehaus.plexus.classworlds.realm.ClassRealm;
   
   /*
    * Copyright 2001-2006 Codehaus Foundation.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  /**
   * The exception which is thrown by a component repository when
   * the requested component cannot be found.
   *
   * @author Jason van Zyl
   */
  public class ComponentLookupException extends Exception {
      private String LS = System.getProperty("line.separator");
  
      private String role;
  
      private String roleHint;
  
      private ClassRealm realm;
  
      public ComponentLookupException(String message, String role, String roleHint) {
          super(message);
  
          this.role = role;
  
          this.roleHint = roleHint;
      }
  
      public ComponentLookupException(String message, String role, String roleHint, Throwable cause) {
          super(message, cause);
  
          this.role = role;
  
          this.roleHint = roleHint;
      }
  
      public ComponentLookupException(String message, String role, String roleHint, ClassRealm realm) {
          super(message);
  
          this.role = role;
  
          this.roleHint = roleHint;
  
          this.realm = realm;
      }
  
      public ComponentLookupException(String message, String role, String roleHint, ClassRealm realm, Throwable cause) {
          super(message, cause);
  
          this.role = role;
  
          this.roleHint = roleHint;
  
          this.realm = realm;
      }
  
      public String getMessage() {
          StringBuilder sb = new StringBuilder()
                  .append(super.getMessage())
                  .append(LS)
                  .append("      role: ")
                  .append(role)
                  .append(LS)
                  .append("  roleHint: ")
                  .append(roleHint)
                  .append(LS)
                  .append("classRealm: ");
  
          if (realm != null) {
              sb.append(realm.getId()).append(LS);
              ByteArrayOutputStream os = new ByteArrayOutputStream(1024);
              PrintStream ps = new PrintStream(os);
              realm.display(ps);
              sb.append(os.toString());
          } else {
              sb.append("none specified");
          }
  
          return sb.toString();
      }
  }