(feat) Impl script engine SPI and refactor AviatorScriptEngine etc., #…

…198

src/main/java/com/googlecode/aviator/AviatorEvaluator.java

@@ -47,7 +47,7 @@ public final class AviatorEvaluator {
   /**
    * Aviator version
    */
-  public static final String VERSION = "3.0.0";
+  public static final String VERSION = "5.0.0";
 
   /**
    * The global evaluator's functions map.

src/main/java/com/googlecode/aviator/AviatorEvaluatorInstance.java

@@ -17,7 +17,6 @@
 package com.googlecode.aviator;
 
 
-import java.io.BufferedReader;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
@@ -138,6 +137,7 @@
 import com.googlecode.aviator.utils.Env;
 import com.googlecode.aviator.utils.LRUMap;
 import com.googlecode.aviator.utils.Reflector;
+import com.googlecode.aviator.utils.Utils;
 
 
 /**
@@ -210,14 +210,9 @@ public Expression compileScript(final String path, final boolean cached) throws
   public Expression compileScript(final String cacheKey, final File file, final boolean cached)
       throws IOException {
     try (InputStream in = new FileInputStream(file);
-        Reader fr = new InputStreamReader(in, Charset.forName("utf-8"));
-        BufferedReader reader = new BufferedReader(fr)) {
-      StringBuilder script = new StringBuilder();
-      String line = null;
-      while ((line = reader.readLine()) != null) {
-        script.append(line).append(Constants.NEWLINE);
-      }
-      return compile(cacheKey, script.toString(), cached);
+        Reader reader = new InputStreamReader(in, Charset.forName("utf-8"));) {
+
+      return compile(cacheKey, Utils.readFully(reader), cached);
     }
   }
 

src/main/java/com/googlecode/aviator/BaseExpression.java

@@ -46,19 +46,35 @@ public BaseExpression(final AviatorEvaluatorInstance instance, final List<String
     this.varNames = new ArrayList<String>(tmp);
   }
 
+  private class SymbolHashMap extends HashMap<String, Object> {
+
+    private static final long serialVersionUID = 5951510458689965590L;
+
+    public SymbolHashMap(final int initialCapacity) {
+      super(initialCapacity);
+    }
+
+    @Override
+    public Object put(String key, final Object value) {
+      Variable var = null;
+      if (BaseExpression.this.symbolTable != null
+          && (var = BaseExpression.this.symbolTable.getVariable(key)) != null) {
+        key = var.getLexeme();
+      }
+      return super.put(key, value);
+    }
+
+  }
+
   @Override
   public Map<String, Object> newEnv(final Object... args) {
     if (args != null && args.length % 2 != 0) {
       throw new IllegalArgumentException("Expect arguments number is even.");
     }
-    Map<String, Object> env = new HashMap<>(args != null ? args.length : 10);
+    Map<String, Object> env = new SymbolHashMap(args != null ? args.length : 10);
     if (args != null) {
       for (int i = 0; i < args.length; i += 2) {
         String key = (String) args[i];
-        Variable var = null;
-        if (this.symbolTable != null && (var = this.symbolTable.getVariable(key)) != null) {
-          key = var.getLexeme();
-        }
         env.put(key, args[i + 1]);
       }
     }

src/main/java/com/googlecode/aviator/script/AviatorScriptEngine.java

@@ -1,5 +1,6 @@
 package com.googlecode.aviator.script;
 
+import java.io.IOException;
 import java.io.Reader;
 import javax.script.AbstractScriptEngine;
 import javax.script.Bindings;
@@ -11,38 +12,57 @@
 import javax.script.SimpleBindings;
 import com.googlecode.aviator.AviatorEvaluator;
 import com.googlecode.aviator.AviatorEvaluatorInstance;
+import com.googlecode.aviator.utils.Utils;
 
 
 /**
- * Aviator Expression engine
+ * Aviator script engine
  *
  * @author [email protected]
+ * @author dennis([email protected])
  * @date 2011-1-18 上午11:03:34
  * @version
  */
 public class AviatorScriptEngine extends AbstractScriptEngine implements Compilable {
 
-  // 缓存编译结果
   private boolean cached = true;
   private final AviatorScriptEngineFactory factory;
-  private AviatorEvaluatorInstance evaluator;
+  private final AviatorEvaluatorInstance engine;
 
 
-  public AviatorScriptEngine(AviatorScriptEngineFactory factory) {
+  public AviatorScriptEngine() {
+    super();
+    this.factory = AviatorScriptEngineFactory.newInstance();
+    this.engine = AviatorEvaluator.newInstance();
+  }
+
+
+  public AviatorScriptEngine(final Bindings n) {
+    super(n);
+    this.factory = AviatorScriptEngineFactory.newInstance();
+    this.engine = AviatorEvaluator.newInstance();
+  }
+
+
+  public AviatorScriptEngine(final AviatorScriptEngineFactory factory) {
     this.factory = factory;
-    this.evaluator = AviatorEvaluator.newInstance();
+    this.engine = AviatorEvaluator.newInstance();
   }
 
 
   @Override
-  public CompiledScript compile(String script) throws ScriptException {
-    return new CompiledAviatorScript(this, evaluator.compile(script, this.cached));
+  public CompiledScript compile(final String script) throws ScriptException {
+    return new CompiledAviatorScript(this, this.engine.compile(script, this.cached));
   }
 
 
   @Override
-  public CompiledScript compile(Reader script) throws ScriptException {
-    throw new UnsupportedOperationException();
+  public CompiledScript compile(final Reader script) throws ScriptException {
+    try {
+      return this.compile(Utils.readFully(script));
+    } catch (IOException e) {
+      throw new ScriptException(e);
+    }
   }
 
 
@@ -51,16 +71,19 @@ public Bindings createBindings() {
     return new SimpleBindings();
   }
 
-
   @Override
-  public Object eval(String script, ScriptContext context) throws ScriptException {
+  public Object eval(final String script, final ScriptContext context) throws ScriptException {
     return this.compile(script).eval(context);
   }
 
 
   @Override
-  public Object eval(Reader reader, ScriptContext context) throws ScriptException {
-    throw new UnsupportedOperationException();
+  public Object eval(final Reader reader, final ScriptContext context) throws ScriptException {
+    try {
+      return eval(Utils.readFully(reader), context);
+    } catch (IOException e) {
+      throw new ScriptException(e);
+    }
   }
 
 
@@ -75,7 +98,12 @@ public boolean isCached() {
   }
 
 
-  public void setCached(boolean cached) {
+  /**
+   * Setting whether to cache the compiled exprssion, defualt is true(caching).
+   *
+   * @param cached true means enable caching.
+   */
+  public void setCached(final boolean cached) {
     this.cached = cached;
   }
 }

src/main/java/com/googlecode/aviator/script/AviatorScriptEngineFactory.java

@@ -11,6 +11,7 @@
 
 
 /**
+ * Aviator script engine factory.
  * 
  * @author [email protected]
  * @author dennis
@@ -19,22 +20,27 @@
  */
 public class AviatorScriptEngineFactory implements ScriptEngineFactory {
 
-  private static final List<String> extensions =
-      Collections.unmodifiableList(Arrays.asList(new String[] {}));
+  private static final List<String> extensions = Collections.unmodifiableList(Arrays.asList(".av"));
   private static final List<String> mimeTypes =
-      Collections.unmodifiableList(Arrays.asList(new String[] {"text/aviator"}));
-  private static final List<String> names =
-      Collections.unmodifiableList(Arrays.asList(new String[] {"Aviator", "aviator"}));
+      Collections.unmodifiableList(Arrays.asList("text/aviator"));
+  private static final List<String> names = Collections
+      .unmodifiableList(Arrays.asList("Aviator", "aviator", "aviatorscript", "AviatorScript"));
 
   private static final Map<String, String> parameterMap = new HashMap<String, String>();
   static {
     parameterMap.put(ScriptEngine.ENGINE, "Aviator");
     parameterMap.put(ScriptEngine.ENGINE_VERSION, AviatorEvaluator.VERSION);
-    parameterMap.put(ScriptEngine.LANGUAGE, "A high performance expression evaluator for java");
+    parameterMap.put(ScriptEngine.LANGUAGE,
+        "A high performance scripting language hosted on the JVM");
     parameterMap.put(ScriptEngine.LANGUAGE_VERSION, AviatorEvaluator.VERSION);
   }
 
 
+  public static final AviatorScriptEngineFactory newInstance() {
+    return new AviatorScriptEngineFactory();
+  }
+
+
   @Override
   public String getEngineName() {
     return parameterMap.get(ScriptEngine.ENGINE);
@@ -66,7 +72,7 @@ public String getLanguageVersion() {
 
 
   @Override
-  public String getMethodCallSyntax(String obj, String m, String... args) {
+  public String getMethodCallSyntax(final String obj, final String m, final String... args) {
     StringBuilder sb = new StringBuilder(m);
     sb.append("(").append(obj);
     if (args != null) {
@@ -93,20 +99,24 @@ public List<String> getNames() {
 
 
   @Override
-  public String getOutputStatement(String toDisplay) {
+  public String getOutputStatement(final String toDisplay) {
     return "print(+" + toDisplay + ")";
   }
 
 
   @Override
-  public Object getParameter(String key) {
+  public Object getParameter(final String key) {
     return parameterMap.get(key);
   }
 
 
   @Override
-  public String getProgram(String... statements) {
-    return null;
+  public String getProgram(final String... statements) {
+    StringBuilder sb = new StringBuilder();
+    for (String stmt : statements) {
+      sb.append(stmt).append(";");
+    }
+    return sb.toString();
   }
 
 

src/main/java/com/googlecode/aviator/script/CompiledAviatorScript.java

@@ -1,6 +1,5 @@
 package com.googlecode.aviator.script;
 
-import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Map;
 import java.util.Set;
@@ -13,8 +12,10 @@
 
 
 /**
- * 
+ * A compiled aviator script.
+ *
  * @author [email protected]
+ * @author dennis([email protected])
  * @date 2011-1-18 上午11:03:34
  * @version
  */
@@ -24,27 +25,26 @@ public class CompiledAviatorScript extends CompiledScript {
   private final Expression expression;
 
 
-  CompiledAviatorScript(AviatorScriptEngine engine, Expression expression) {
+  CompiledAviatorScript(final AviatorScriptEngine engine, final Expression expression) {
     this.engine = engine;
     this.expression = expression;
   }
 
 
   @Override
-  @SuppressWarnings("unchecked")
-  public Object eval(ScriptContext context) throws ScriptException {
+  public Object eval(final ScriptContext context) throws ScriptException {
     try {
-      Map<String, Object> map = new HashMap<String, Object>();
-      for (Iterator it = context.getScopes().iterator(); it.hasNext();) {
-        int scope = ((Integer) it.next()).intValue();
+      Map<String, Object> env = this.expression.newEnv();
+      for (Iterator<Integer> it = context.getScopes().iterator(); it.hasNext();) {
+        int scope = it.next().intValue();
         Bindings bindings = context.getBindings(scope);
-        Set keys = bindings.keySet();
+        Set<String> keys = bindings.keySet();
 
-        for (Object key : keys) {
-          map.put((String) key, bindings.get(key));
+        for (String key : keys) {
+          env.put(key, bindings.get(key));
         }
       }
-      return this.expression.execute(map);
+      return this.expression.execute(env);
     } catch (Exception e) {
       throw new ScriptException(e);
     }

src/main/java/com/googlecode/aviator/utils/Utils.java

@@ -0,0 +1,28 @@
+package com.googlecode.aviator.utils;
+
+import java.io.IOException;
+import java.io.Reader;
+
+/**
+ * Some helper methods.
+ *
+ * @author dennis([email protected])
+ *
+ */
+public class Utils {
+  private Utils() {
+
+  }
+
+  public static String readFully(final Reader reader) throws IOException {
+    final char[] arr = new char[16 * 1024];
+    final StringBuilder buf = new StringBuilder();
+    int numChars;
+
+    while ((numChars = reader.read(arr, 0, arr.length)) > 0) {
+      buf.append(arr, 0, numChars);
+    }
+
+    return buf.toString();
+  }
+}

src/main/resources/META-INF/services/javax.script.ScriptEngineFactory

@@ -0,0 +1 @@
+com.googlecode.aviator.script.AviatorScriptEngineFactory

src/test/java/com/googlecode/aviator/ScriptEngineTest.java

@@ -0,0 +1,20 @@
+package com.googlecode.aviator;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import javax.script.ScriptEngine;
+import javax.script.ScriptEngineManager;
+import org.junit.Test;
+
+public class ScriptEngineTest {
+
+  @Test
+  public void testScriptEngine() throws Exception {
+    final ScriptEngineManager m = new ScriptEngineManager();
+    final ScriptEngine engine = m.getEngineByName("aviator");
+    assertNotNull(engine);
+
+    assertEquals(3, engine.eval("1+2"));
+    assertEquals(6, engine.eval("square = lambda(x) -> x*2 end; square(3)"));
+  }
+}