//========================================================================
//Copyright 2007-2009 David Yu dyuproject@gmail.com
//------------------------------------------------------------------------
//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.
//========================================================================
package com.dyuproject.protostuff.parser;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.Reader;
import java.net.URL;
import org.antlr.runtime.ANTLRInputStream;
import org.antlr.runtime.ANTLRReaderStream;
import org.antlr.runtime.CommonTokenStream;
/**
* Utility for loading protos from various input.
*
* @author David Yu
* @created Dec 24, 2009
*/
public final class ProtoUtil
{
private ProtoUtil() {}
/**
* Loads the proto from an {@link ANTLRReaderStream}.
*/
public static void loadFrom(ANTLRReaderStream input, Proto target) throws Exception
{
// Create an ExprLexer that feeds from that stream
ProtoLexer lexer = new ProtoLexer(input);
// Create a stream of tokens fed by the lexer
CommonTokenStream tokens = new CommonTokenStream(lexer);
// Create a parser that feeds off the token stream
ProtoParser parser = new ProtoParser(tokens);
// Begin parsing at rule parse
parser.parse(target);
}
/**
* Loads the proto from an {@link InputStream}.
*/
public static void loadFrom(InputStream in, Proto target) throws Exception
{
loadFrom(new ANTLRInputStream(in), target);
}
/**
* Loads the proto from a {@link Reader}.
*/
public static void loadFrom(Reader reader, Proto target) throws Exception
{
loadFrom(new ANTLRReaderStream(reader), target);
}
public static Proto parseProto(File file)
{
Proto proto = new Proto(file);
try
{
loadFrom(file, proto);
}
catch (Exception e)
{
throw new RuntimeException(e);
}
return proto;
}
public static void loadFrom(File file, Proto target) throws Exception
{
FileInputStream in = new FileInputStream(file);
try
{
loadFrom(in, target);
}
finally
{
in.close();
}
}
public static void loadFrom(URL resource, Proto target) throws Exception
{
InputStream in = resource.openStream();
try
{
loadFrom(in, target);
}
finally
{
in.close();
}
}
public static StringBuilder toCamelCase(String name)
{
StringBuilder buffer = new StringBuilder();
int toUpper = 0;
char c;
for(int i=0, len=name.length(); i<len;)
{
c= name.charAt(i++);
if(c=='_')
{
if(i==len)
break;
if(buffer.length()!=0)
toUpper++;
continue;
}
else if(toUpper!=0)
{
if(c>96 && c<123)
{
buffer.append((char)(c-32));
toUpper = 0;
}
else if(c>64 && c<91)
{
buffer.append(c);
toUpper = 0;
}
else
{
while(toUpper>0)
{
buffer.append('_');
toUpper--;
}
buffer.append(c);
}
}
else
{
if(buffer.length()==0 && c>64 && c<91)
buffer.append((char)(c+32));
else
buffer.append(c);
}
}
return buffer;
}
public static StringBuilder toPascalCase(String name)
{
StringBuilder buffer = toCamelCase(name);
char c = buffer.charAt(0);
if(c>96 && c<123)
buffer.setCharAt(0, (char)(c-32));
return buffer;
}
public static StringBuilder toUnderscoreCase(String name)
{
StringBuilder buffer = new StringBuilder();
boolean toLower = false, appendUnderscore=false;
for(int i=0, len=name.length(); i<len;)
{
char c = name.charAt(i++);
if(c=='_')
{
if(i==len)
break;
if(buffer.length()!=0)
appendUnderscore = true;
continue;
}
if(appendUnderscore)
buffer.append('_');
if(c>96 && c<123)
{
buffer.append(c);
toLower = true;
}
else if(c>64 && c<91)
{
if(toLower)
{
// avoid duplicate underscore
if(!appendUnderscore)
buffer.append('_');
toLower = false;
}
buffer.append((char)(c+32));
}
else
{
buffer.append(c);
toLower = false;
}
appendUnderscore = false;
}
return buffer;
}
public static void main(String[] args)
{
String[] gg = {"foo_bar_baz", "fooBarBaz", "FooBarBaz", "foo_bar_baz", "____Foo____Bar___Baz____"};
for(String g : gg)
{
System.err.println(toCamelCase(g));
System.err.println(toPascalCase(g));
System.err.println(toUnderscoreCase(g));
System.err.println(toUnderscoreCase(g).toString().toUpperCase());
}
}
}