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/*******************************************************************************
* Copyright (c) 2013 LuaJ. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
******************************************************************************/
package org.luaj.vm2.script;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintStream;
import java.io.Reader;
import java.io.Writer;
import javax.script.ScriptContext;
import javax.script.SimpleScriptContext;
import org.luaj.vm2.Globals;
import org.luaj.vm2.lib.jse.JsePlatform;
import org.luaj.vm2.luajc.LuaJC;
/**
* Context for LuaScriptEngine execution which maintains its own Globals,
* and manages the input and output redirection.
*/
public class LuajContext extends SimpleScriptContext implements ScriptContext {
/** Globals for this context instance. */
public final Globals globals;
/** The initial value of globals.STDIN */
private final InputStream stdin;
/** The initial value of globals.STDOUT */
private final PrintStream stdout;
/** The initial value of globals.STDERR */
private final PrintStream stderr;
/** Construct a LuajContext with its own globals which may
* be debug globals depending on the value of the system
* property 'org.luaj.debug'
*
* If the system property 'org.luaj.debug' is set, the globals
* created will be a debug globals that includes the debug
* library. This may provide better stack traces, but may
* have negative impact on performance.
*/
public LuajContext() {
this("true".equals(System.getProperty("org.luaj.debug")),
"true".equals(System.getProperty("org.luaj.luajc")));
}
/** Construct a LuajContext with its own globals, which
* which optionally are debug globals, and optionally use the
* luajc direct lua to java bytecode compiler.
*
* If createDebugGlobals is set, the globals
* created will be a debug globals that includes the debug
* library. This may provide better stack traces, but may
* have negative impact on performance.
* @param createDebugGlobals true to create debug globals,
* false for standard globals.
* @param useLuaJCCompiler true to use the luajc compiler,
* reqwuires bcel to be on the class path.
*/
public LuajContext(boolean createDebugGlobals, boolean useLuaJCCompiler) {
globals = createDebugGlobals?
JsePlatform.debugGlobals():
JsePlatform.standardGlobals();
if (useLuaJCCompiler)
LuaJC.install(globals);
stdin = globals.STDIN;
stdout = globals.STDOUT;
stderr = globals.STDERR;
}
@Override
public void setErrorWriter(Writer writer) {
globals.STDERR = writer != null?
new PrintStream(new WriterOutputStream(writer)):
stderr;
}
@Override
public void setReader(Reader reader) {
globals.STDIN = reader != null?
new ReaderInputStream(reader):
stdin;
}
@Override
public void setWriter(Writer writer) {
globals.STDOUT = writer != null?
new PrintStream(new WriterOutputStream(writer)):
stdout;
}
static final class WriterOutputStream extends OutputStream {
final Writer w;
WriterOutputStream(Writer w) {
this.w = w;
}
public void write(int b) throws IOException {
w.write(b);
}
}
static final class ReaderInputStream extends InputStream {
final Reader r;
ReaderInputStream(Reader r) {
this.r = r;
}
public int read() throws IOException {
return r.read();
}
}
}