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A Java implementation of the Amazon Ion data notation.
/*
* Copyright 2007-2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* or in the "license" file accompanying this file. This file 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 com.amazon.ion.impl.bin;
import static com.amazon.ion.SystemSymbols.IMPORTS;
import static com.amazon.ion.SystemSymbols.IMPORTS_SID;
import static com.amazon.ion.SystemSymbols.ION;
import static com.amazon.ion.SystemSymbols.ION_1_0;
import static com.amazon.ion.SystemSymbols.ION_1_0_MAX_ID;
import static com.amazon.ion.SystemSymbols.ION_1_0_SID;
import static com.amazon.ion.SystemSymbols.ION_SHARED_SYMBOL_TABLE;
import static com.amazon.ion.SystemSymbols.ION_SHARED_SYMBOL_TABLE_SID;
import static com.amazon.ion.SystemSymbols.ION_SID;
import static com.amazon.ion.SystemSymbols.ION_SYMBOL_TABLE;
import static com.amazon.ion.SystemSymbols.ION_SYMBOL_TABLE_SID;
import static com.amazon.ion.SystemSymbols.MAX_ID;
import static com.amazon.ion.SystemSymbols.MAX_ID_SID;
import static com.amazon.ion.SystemSymbols.NAME;
import static com.amazon.ion.SystemSymbols.NAME_SID;
import static com.amazon.ion.SystemSymbols.SYMBOLS;
import static com.amazon.ion.SystemSymbols.SYMBOLS_SID;
import static com.amazon.ion.SystemSymbols.VERSION;
import static com.amazon.ion.SystemSymbols.VERSION_SID;
import static java.util.Arrays.asList;
import static java.util.Collections.unmodifiableList;
import static java.util.Collections.unmodifiableMap;
import com.amazon.ion.IonException;
import com.amazon.ion.SymbolTable;
import com.amazon.ion.SymbolToken;
import com.amazon.ion.impl._Private_Utils;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;
/**
* Utilities for dealing with {@link SymbolToken} and {@link SymbolTable}.
*/
/*package*/ class Symbols
{
private Symbols() {}
/** Constructs a token with a non-null name and positive value. */
public static SymbolToken symbol(final String name, final int val)
{
if (name == null) { throw new NullPointerException(); }
if (val <= 0) { throw new IllegalArgumentException("Symbol value must be positive: " + val); }
return _Private_Utils.newSymbolToken(name, val);
}
/** Lazy iterator over the symbol names of an iterator of symbol tokens. */
public static Iterator symbolNameIterator(final Iterator tokenIter)
{
return new Iterator()
{
public boolean hasNext()
{
return tokenIter.hasNext();
}
public String next()
{
return tokenIter.next().getText();
}
public void remove()
{
throw new UnsupportedOperationException();
}
};
}
private static final List SYSTEM_TOKENS = unmodifiableList(
asList(
symbol(ION, ION_SID)
, symbol(ION_1_0, ION_1_0_SID)
, symbol(ION_SYMBOL_TABLE, ION_SYMBOL_TABLE_SID)
, symbol(NAME, NAME_SID)
, symbol(VERSION, VERSION_SID)
, symbol(IMPORTS, IMPORTS_SID)
, symbol(SYMBOLS, SYMBOLS_SID)
, symbol(MAX_ID, MAX_ID_SID)
, symbol(ION_SHARED_SYMBOL_TABLE, ION_SHARED_SYMBOL_TABLE_SID)
)
);
/** Returns a symbol token for a system SID. */
public static SymbolToken systemSymbol(final int sid) {
if (sid < 1 || sid > ION_1_0_MAX_ID)
{
throw new IllegalArgumentException("No such system SID: " + sid);
}
return SYSTEM_TOKENS.get(sid - 1);
}
private static final Map SYSTEM_TOKEN_MAP;
static {
final Map symbols = new HashMap();
for (final SymbolToken token : SYSTEM_TOKENS)
{
symbols.put(token.getText(), token);
}
SYSTEM_TOKEN_MAP = unmodifiableMap(symbols);
}
private static SymbolTable SYSTEM_SYMBOL_TABLE = new AbstractSymbolTable(ION, 1)
{
public SymbolTable[] getImportedTables()
{
return null;
}
public int getImportedMaxId()
{
return 0;
}
public boolean isSystemTable()
{
return true;
}
public boolean isSubstitute()
{
return false;
}
public boolean isSharedTable()
{
return true;
}
public boolean isReadOnly()
{
return true;
}
public boolean isLocalTable()
{
return false;
}
public SymbolToken intern(final String text)
{
final SymbolToken token = SYSTEM_TOKEN_MAP.get(text);
if (token == null)
{
throw new IonException("Cannot intern new symbol into system symbol table");
}
return token;
}
public String findKnownSymbol(int id)
{
if (id < 1)
{
throw new IllegalArgumentException("SID cannot be less than 1: " + id);
}
if (id > ION_1_0_MAX_ID)
{
return null;
}
return SYSTEM_TOKENS.get(id - 1).getText();
}
public SymbolToken find(String text)
{
return SYSTEM_TOKEN_MAP.get(text);
}
public SymbolTable getSystemSymbolTable()
{
return this;
}
public int getMaxId()
{
return ION_1_0_MAX_ID;
}
public Iterator iterateDeclaredSymbolNames()
{
return symbolNameIterator(SYSTEM_TOKENS.iterator());
}
};
/** Returns a representation of the system symbol table. */
public static SymbolTable systemSymbolTable()
{
return SYSTEM_SYMBOL_TABLE;
}
/** Returns the system symbols as a collection. */
public static Collection systemSymbols()
{
return SYSTEM_TOKENS;
}
/** Returns a substitute shared symbol table where none of the symbols are known. */
public static SymbolTable unknownSharedSymbolTable(final String name,
final int version,
final int maxId)
{
return new AbstractSymbolTable(name, version)
{
public Iterator iterateDeclaredSymbolNames()
{
return new Iterator()
{
int id = 1;
public boolean hasNext()
{
return id <= maxId;
}
public String next()
{
if (!hasNext())
{
throw new NoSuchElementException();
}
// all symbols are unknown
id++;
return null;
}
public void remove()
{
throw new UnsupportedOperationException();
}
};
}
public boolean isSystemTable()
{
return false;
}
public boolean isSubstitute()
{
return true;
}
public boolean isSharedTable()
{
return true;
}
public boolean isReadOnly()
{
return true;
}
public boolean isLocalTable()
{
return false;
}
public SymbolToken intern(String text)
{
throw new UnsupportedOperationException(
"Cannot intern into substitute unknown shared symbol table: "
+ name + " version " + version
);
}
public SymbolTable getSystemSymbolTable()
{
return systemSymbolTable();
}
public int getMaxId()
{
return maxId;
}
public SymbolTable[] getImportedTables()
{
return null;
}
public int getImportedMaxId()
{
return 0;
}
public String findKnownSymbol(int id)
{
return null;
}
public SymbolToken find(String text)
{
return null;
}
};
}
}