Java开发之——Java6的新特性

原文请参考:Java6的新特性

本文梳理了下java6的新特性,相对于java5而言,java6的特性显得少些,分量也不那么重,相当于java5是windows xp,java6有点像vista。

特性列表

  • JSR223脚本引擎

  • JSR199--Java Compiler API

  • JSR269--Pluggable Annotation Processing API

  • 支持JDBC4.0规范

  • JAX-WS 2.0规范

    JSR223脚本引擎

  • 基本使用

      public class BasicScripting 
          {
                public void greet() throws ScriptException
               {
                   ScriptEngineManager manager = new ScriptEngineManager();
                  //支持通过名称、文件扩展名、MIMEtype查找
                  ScriptEngine engine = manager.getEngineByName("JavaScript");
                  //engine = manager.getEngineByExtension("js");
                  //engine = manager.getEngineByMimeType("text/javascript");
                  if (engine == null) 
                      {
                         throw new RuntimeException("找不到JavaScript语言执行引擎。");
                      }
                          engine.eval("println('Hello!');");
               }
              public static void main(String[] args)
               {
                  try {
                        new BasicScripting().greet();
                      } catch (ScriptException ex) 
                      {
                             Logger.getLogger(BasicScripting.class.getName()).log(Level.SEVERE, null, ex);
                      }
                  }
           }
    
  • 绑定上下文

      public class ScriptContextBindings extends JsScriptRunner
       {
          public void scriptContextBindings() throws ScriptException 
            {
                  ScriptEngine engine = getJavaScriptEngine();
               ScriptContext context = engine.getContext();
               Bindings bindings1 = engine.createBindings();
               bindings1.put("name", "Alex");
               context.setBindings(bindings1, ScriptContext.GLOBAL_SCOPE);
               Bindings bindings2 = engine.createBindings();
               bindings2.put("name", "Bob");
                  context.setBindings(bindings2, ScriptContext.ENGINE_SCOPE);
                  engine.eval("println(name);");
            }
          public void useScriptContextValues() throws ScriptException 
           {
              ScriptEngine engine = getJavaScriptEngine();
              ScriptContext context = engine.getContext();
              Bindings bindings = context.getBindings(ScriptContext.ENGINE_SCOPE);
              bindings.put("name", "Alex");
              engine.eval("println(name);");
          }
          public void attributeInBindings() throws ScriptException
           {
              ScriptEngine engine = getJavaScriptEngine();
              ScriptContext context = engine.getContext();
              context.setAttribute("name", "Alex", ScriptContext.GLOBAL_SCOPE);
                  engine.eval("println(name);");
           }
          /**
           * @param args the command line arguments
           */
          public static void main(String[] args) throws ScriptException
           {
                  ScriptContextBindings scb = new ScriptContextBindings();
               scb.scriptContextBindings();
               scb.useScriptContextValues();
               scb.attributeInBindings();
              }
      }
    

JSR199--Java Compiler API

public class JavaCompilerAPICompiler 
  {
     public void compile(Path src, Path output) throws IOException 
        {
            JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
            try (StandardJavaFileManager fileManager = compiler.getStandardFileManager(null, null, null))
                 {
                    Iterable<? extends JavaFileObject> compilationUnits = fileManager.getJavaFileObjects(src.toFile());
                    Iterable<String> options = Arrays.asList("-d", output.toString());
                    JavaCompiler.CompilationTask task = compiler.getTask(null, fileManager, null, options, null, compilationUnits);
                    boolean result = task.call();
                }
        }
  }

JSR269--Pluggable Annotation Processing API

一部分是进行注解处理的javax.annotation.processing,另一部分是对程序的静态结构进行建模的javax.lang.model

其他

  • 支持JDBC4.0规范
  • JAX-WS 2.0规范(包括JAXB 2.0)
  • 轻量级HttpServer