Javac之关于方法的选择

最新推荐文章于 2024-07-31 04:27:27 发布

转载最新推荐文章于 2024-07-31 04:27:27 发布 · 98 阅读

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原文链接：http://www.cnblogs.com/extjs4/p/7623140.html

本文详细解析了Java中方法调用的五种形式及其编译和运行时的步骤，包括确定搜索类、方法签名、参数匹配等关键过程，并通过实例说明了如何在不同情况下正确调用方法。

15.12. Method Invocation Expressions

15.12.1. Compile-Time Step 1: Determine Class or Interface to Search 15.12.2. Compile-Time Step 2: Determine Method Signature

15.12.2.1. Identify Potentially Applicable Methods 15.12.2.2. Phase 1: Identify Matching Arity Methods Applicable by Subtyping 15.12.2.3. Phase 2: Identify Matching Arity Methods Applicable by Method Invocation Conversion 15.12.2.4. Phase 3: Identify Applicable Variable Arity Methods 15.12.2.5. Choosing the Most Specific Method 15.12.2.6. Method Result and Throws Types 15.12.2.7. Inferring Type Arguments Based on Actual Arguments 15.12.2.8. Inferring Unresolved Type Arguments

15.12.3. Compile-Time Step 3: Is the Chosen Method Appropriate? 15.12.4. Run-Time Evaluation of Method Invocation

15.12.4.1. Compute Target Reference (If Necessary) 15.12.4.2. Evaluate Arguments 15.12.4.3. Check Accessibility of Type and Method 15.12.4.4. Locate Method to Invoke 15.12.4.5. Create Frame, Synchronize, Transfer Control

方法调用的形式主要有5种：

MethodInvocation:
    MethodName ( ArgumentList_opt )
    Primary . NonWildTypeArguments_opt Identifier ( ArgumentList_opt )
    super . NonWildTypeArguments_opt Identifier ( ArgumentList_opt )
    ClassName . super . NonWildTypeArguments_opt Identifier ( ArgumentList_opt )
    TypeName . NonWildTypeArguments Identifier ( ArgumentList_opt )

举个例子如下：

class A{
	public void test(){}
}


public class TestMethodInvocation extends A{
	
	public void m1(){}
	public static void m2(){}
	
	
	public void test(){
		m1();
		A a = new TestMethodInvocation();
		a.test();
		super.test();
		TestMethodInvocation.m2();
	}
    
	class C{
		public void m(){
			// It is a compile-time error if C is not a lexically enclosing class of the current class.
			TestMethodInvocation.super.test();
		}
	}
}

转载于:https://www.cnblogs.com/extjs4/p/7623140.html