org.apache.xml.resolver.CatalogEntry Maven / Gradle / Ivy
// CatalogEntry.java - Represents Catalog entries
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.
*/
package org.apache.xml.resolver;
import java.util.Hashtable;
import java.util.Vector;
/**
* Represents a Catalog entry.
*
* Instances of this class represent individual entries
* in a Catalog.
*
* Each catalog entry has a unique name and is associated with
* an arbitrary number of arguments (all strings). For example, the
* TR9401 catalog entry "PUBLIC" has two arguments, a public identifier
* and a system identifier. Each entry has a unique numeric type,
* assigned automatically when the entry type is created.
*
* The number and type of catalog entries is maintained
* statically. Catalog classes, or their subclasses, can add
* new entry types, but all Catalog objects share the same global pool
* of types.
*
* Initially there are no valid entries.
*
* @see Catalog
*
* @author Norman Walsh
* [email protected]
*
* @version 1.0
*/
public class CatalogEntry {
/** The nextEntry is the ordinal number of the next entry type. */
protected static int nextEntry = 0;
/**
* The entryTypes vector maps catalog entry names
* (e.g., 'BASE' or 'SYSTEM') to their type (1, 2, etc.).
* Names are case sensitive.
*/
protected static Hashtable entryTypes = new Hashtable();
/** The entryTypes vector maps catalog entry types to the
number of arguments they're required to have. */
protected static Vector entryArgs = new Vector();
/**
* Adds a new catalog entry type.
*
* @param name The name of the catalog entry type. This must be
* unique among all types and is case-sensitive. (Adding a duplicate
* name effectively replaces the old type with the new type.)
* @param numArgs The number of arguments that this entry type
* is required to have. There is no provision for variable numbers
* of arguments.
* @return The type for the new entry.
*/
public static int addEntryType(String name, int numArgs) {
entryTypes.put(name, new Integer(nextEntry));
entryArgs.add(nextEntry, new Integer(numArgs));
nextEntry++;
return nextEntry-1;
}
/**
* Lookup an entry type
*
* @param name The name of the catalog entry type.
* @return The type of the catalog entry with the specified name.
* @throws InvalidCatalogEntryTypeException if no entry has the
* specified name.
*/
public static int getEntryType(String name)
throws CatalogException {
if (!entryTypes.containsKey(name)) {
throw new CatalogException(CatalogException.INVALID_ENTRY_TYPE);
}
Integer iType = (Integer) entryTypes.get(name);
if (iType == null) {
throw new CatalogException(CatalogException.INVALID_ENTRY_TYPE);
}
return iType.intValue();
}
/**
* Find out how many arguments an entry is required to have.
*
* @param name The name of the catalog entry type.
* @return The number of arguments that entry type is required to have.
* @throws InvalidCatalogEntryTypeException if no entry has the
* specified name.
*/
public static int getEntryArgCount(String name)
throws CatalogException {
return getEntryArgCount(getEntryType(name));
}
/**
* Find out how many arguments an entry is required to have.
*
* @param type A valid catalog entry type.
* @return The number of arguments that entry type is required to have.
* @throws InvalidCatalogEntryTypeException if the type is invalid.
*/
public static int getEntryArgCount(int type)
throws CatalogException {
try {
Integer iArgs = (Integer) entryArgs.get(type);
return iArgs.intValue();
} catch (ArrayIndexOutOfBoundsException e) {
throw new CatalogException(CatalogException.INVALID_ENTRY_TYPE);
}
}
/** The entry type of this entry */
protected int entryType = 0;
/** The arguments associated with this entry */
protected Vector args = null;
/**
* Null constructor; something for subclasses to call.
*/
public CatalogEntry() {}
/**
* Construct a catalog entry of the specified type.
*
* @param name The name of the entry type
* @param args A String Vector of arguments
* @throws InvalidCatalogEntryTypeException if no such entry type
* exists.
* @throws InvalidCatalogEntryException if the wrong number of arguments
* is passed.
*/
public CatalogEntry(String name, Vector args)
throws CatalogException {
Integer iType = (Integer) entryTypes.get(name);
if (iType == null) {
throw new CatalogException(CatalogException.INVALID_ENTRY_TYPE);
}
int type = iType.intValue();
try {
Integer iArgs = (Integer) entryArgs.get(type);
if (iArgs.intValue() != args.size()) {
throw new CatalogException(CatalogException.INVALID_ENTRY);
}
} catch (ArrayIndexOutOfBoundsException e) {
throw new CatalogException(CatalogException.INVALID_ENTRY_TYPE);
}
entryType = type;
this.args = args;
}
/**
* Construct a catalog entry of the specified type.
*
* @param type The entry type
* @param args A String Vector of arguments
* @throws InvalidCatalogEntryTypeException if no such entry type
* exists.
* @throws InvalidCatalogEntryException if the wrong number of arguments
* is passed.
*/
public CatalogEntry(int type, Vector args)
throws CatalogException {
try {
Integer iArgs = (Integer) entryArgs.get(type);
if (iArgs.intValue() != args.size()) {
throw new CatalogException(CatalogException.INVALID_ENTRY);
}
} catch (ArrayIndexOutOfBoundsException e) {
throw new CatalogException(CatalogException.INVALID_ENTRY_TYPE);
}
entryType = type;
this.args = args;
}
/**
* Get the entry type.
*
* @return The entry type of the CatalogEntry
*/
public int getEntryType() {
return entryType;
}
/**
* Get an entry argument.
*
* @param argNum The argument number (arguments are numbered from 0).
* @return The specified argument or null if an invalid argNum is
* provided.
*/
public String getEntryArg(int argNum) {
try {
String arg = (String) args.get(argNum);
return arg;
} catch (ArrayIndexOutOfBoundsException e) {
return null;
}
}
/**
* Set an entry argument.
*
* Catalogs sometimes need to adjust the catlog entry parameters,
* for example to make a relative URI absolute with respect to the
* current base URI. But in general, this function should only be
* called shortly after object creation to do some sort of cleanup.
* Catalog entries should not mutate over time.
*
* @param argNum The argument number (arguments are numbered from 0).
* @throws ArrayIndexOutOfBoundsException if an invalid argument
* number is provided.
*/
public void setEntryArg(int argNum, String newspec)
throws ArrayIndexOutOfBoundsException {
args.set(argNum, newspec);
}
}