| /* |
| * 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.tinkerpop.gremlin.jsr223; |
| |
| import javax.script.Bindings; |
| import javax.script.ScriptContext; |
| import javax.script.SimpleBindings; |
| import java.io.Reader; |
| import java.io.Writer; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.Objects; |
| |
| /** |
| * A {@code ScriptContext} that doesn't create new instances of {@code Reader} and {@code Writer} classes on |
| * initialization. |
| * |
| * @author Stephen Mallette (http://stephen.genoprime.com) |
| */ |
| public class GremlinScriptContext implements ScriptContext { |
| |
| private Writer writer; |
| private Writer errorWriter; |
| private Reader reader; |
| private Bindings engineScope; |
| private Bindings globalScope; |
| private static List<Integer> scopes; |
| |
| static { |
| scopes = new ArrayList<>(2); |
| scopes.add(ENGINE_SCOPE); |
| scopes.add(GLOBAL_SCOPE); |
| scopes = Collections.unmodifiableList(scopes); |
| } |
| |
| /** |
| * Create a {@code GremlinScriptContext}. |
| */ |
| public GremlinScriptContext(final Reader in, final Writer out, final Writer error) { |
| engineScope = new SimpleBindings(); |
| globalScope = null; |
| reader = in; |
| writer = out; |
| errorWriter = error; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public void setBindings(final Bindings bindings, final int scope) { |
| switch (scope) { |
| case ENGINE_SCOPE: |
| if (null == bindings) throw new NullPointerException("Engine scope cannot be null."); |
| engineScope = bindings; |
| break; |
| case GLOBAL_SCOPE: |
| globalScope = bindings; |
| break; |
| default: |
| throw new IllegalArgumentException("Invalid scope value."); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public Object getAttribute(final String name) { |
| checkName(name); |
| if (engineScope.containsKey(name)) { |
| return getAttribute(name, ENGINE_SCOPE); |
| } else if (globalScope != null && globalScope.containsKey(name)) { |
| return getAttribute(name, GLOBAL_SCOPE); |
| } |
| |
| return null; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public Object getAttribute(final String name, final int scope) { |
| checkName(name); |
| switch (scope) { |
| case ENGINE_SCOPE: |
| return engineScope.get(name); |
| case GLOBAL_SCOPE: |
| return globalScope != null ? globalScope.get(name) : null; |
| default: |
| throw new IllegalArgumentException("Illegal scope value."); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public Object removeAttribute(final String name, final int scope) { |
| checkName(name); |
| switch (scope) { |
| case ENGINE_SCOPE: |
| return getBindings(ENGINE_SCOPE) != null ? getBindings(ENGINE_SCOPE).remove(name) : null; |
| case GLOBAL_SCOPE: |
| return getBindings(GLOBAL_SCOPE) != null ? getBindings(GLOBAL_SCOPE).remove(name) : null; |
| default: |
| throw new IllegalArgumentException("Illegal scope value."); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public void setAttribute(final String name, final Object value, final int scope) { |
| checkName(name); |
| switch (scope) { |
| case ENGINE_SCOPE: |
| engineScope.put(name, value); |
| return; |
| case GLOBAL_SCOPE: |
| if (globalScope != null) globalScope.put(name, value); |
| return; |
| default: |
| throw new IllegalArgumentException("Illegal scope value."); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public int getAttributesScope(final String name) { |
| checkName(name); |
| if (engineScope.containsKey(name)) |
| return ENGINE_SCOPE; |
| else if (globalScope != null && globalScope.containsKey(name)) |
| return GLOBAL_SCOPE; |
| else |
| return -1; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public Bindings getBindings(final int scope) { |
| if (scope == ENGINE_SCOPE) |
| return engineScope; |
| else if (scope == GLOBAL_SCOPE) |
| return globalScope; |
| else |
| throw new IllegalArgumentException("Illegal scope value."); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public List<Integer> getScopes() { |
| return scopes; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public Writer getWriter() { |
| return writer; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public Reader getReader() { |
| return reader; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public void setReader(final Reader reader) { |
| this.reader = reader; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public void setWriter(final Writer writer) { |
| this.writer = writer; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public Writer getErrorWriter() { |
| return errorWriter; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public void setErrorWriter(final Writer writer) { |
| this.errorWriter = writer; |
| } |
| |
| private void checkName(final String name) { |
| Objects.requireNonNull(name); |
| if (name.isEmpty()) throw new IllegalArgumentException("name cannot be empty"); |
| } |
| } |