专业嵌入式软件开发番禺seo
Java语言特性系列
序
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
1、JSR223脚本引擎
Scripting for the Java Platform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();
}
}
2、JSR199--Java Compiler APIpublic 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 options = Arrays.asList("-d", output.toString());
JavaCompiler.CompilationTask task = compiler.getTask(null, fileManager, null, options, null, compilationUnits);
boolean result = task.call();
}
}
}
3、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
4、其他支持JDBC4.0规范
JAX-WS 2.0规范(包括JAXB 2.0)
轻量级HttpServer
参考