NonnullAspect

NonnullAspect.java

package com.fxdd.common.aspects.notnull;

import java.lang.annotation.Annotation;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.reflect.CodeSignature;
import org.aspectj.lang.reflect.ConstructorSignature;
import org.aspectj.lang.reflect.MethodSignature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.annotation.Nonnull;

@Aspect
public class NonnullAspect {
    private static final Logger logger = LoggerFactory.getLogger(NonnullAspect.class);

    @Before("execution(* *..*.*(@javax.annotation.Nonnull (*), ..)) && args(value, ..)")
    public void notNull_0(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 0);
    }

    @Before("execution(* *..*.*(*, @javax.annotation.Nonnull (*), ..)) && args(*, value, ..)")
    public void notNull_1(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 1);
    }

    @Before("execution(* *..*.*(*, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, value, ..)")
    public void notNull_2(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 2);
    }

    @Before("execution(* *..*.*(*, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, value, ..)")
    public void notNull_3(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 3);
    }

    @Before("execution(* *..*.*(*, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, value, ..)")
    public void notNull_4(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 4);
    }

    @Before("execution(* *..*.*(*, *, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, *, value, ..)")
    public void notNull_5(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 5);
    }

    @Before("execution(* *..*.*(*, *, *, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, *, *, value, ..)")
    public void notNull_6(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 6);
    }

    @Before("execution(* *..*.*(*, *, *, *, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, *, *, *, value, ..)")
    public void notNull_7(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 7);
    }

    @Before("execution(* *..*.*(*, *, *, *, *, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, *, *, *, *, value, ..)")
    public void notNull_8(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 8);
    }

    @Before("execution(* *..*.*(*, *, *, *, *, *, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, *, *, *, *, *, value, ..)")
    public void notNull_9(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 9);
    }

    @Before("execution(* *..*.*(*, *, *, *, *, *, *, *, *, *, .., @javax.annotation.Nonnull (*), ..))")
    public void notNull_moreThan9(JoinPoint point) throws Throwable {
        final MethodSignature signature = (MethodSignature) point.getSignature();
        final Annotation[][] parameterAnnotations = signature.getMethod().getParameterAnnotations();
        for (int i=10; i< parameterAnnotations.length; i++){
            for (final Annotation annotation : parameterAnnotations[i]) {
                if (annotation instanceof Nonnull){
                    checkNotNull(point, point.getArgs()[i], i);
                }
            }
        }
    }
    
    @Before("execution(*..*.new(@javax.annotation.Nonnull (*), ..)) && args(value, ..)")
    public void notNull_new_0(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 0);
    }

    @Before("execution(*..*.new(*, @javax.annotation.Nonnull (*), ..)) && args(*, value, ..)")
    public void notNull_new_1(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 1);
    }

    @Before("execution(*..*.new(*, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, value, ..)")
    public void notNull_new_2(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 2);
    }

    @Before("execution(*..*.new(*, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, value, ..)")
    public void notNull_new_3(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 3);
    }

    @Before("execution(*..*.new(*, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, value, ..)")
    public void notNull_new_4(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 4);
    }

    @Before("execution(*..*.new(*, *, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, *, value, ..)")
    public void notNull_new_5(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 5);
    }

    @Before("execution(*..*.new(*, *, *, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, *, *, value, ..)")
    public void notNull_new_6(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 6);
    }

    @Before("execution(*..*.new(*, *, *, *, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, *, *, *, value, ..)")
    public void notNull_new_7(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 7);
    }

    @Before("execution(*..*.new(*, *, *, *, *, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, *, *, *, *, value, ..)")
    public void notNull_new_8(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 8);
    }

    @Before("execution(*..*.new(*, *, *, *, *, *, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, *, *, *, *, *, value, ..)")
    public void notNull_new_9(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 9);
    }

    @Before("execution(*..*.new(*, *, *, *, *, *, *, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, *, *, *, *, *, *, value, ..)")
    public void notNull_new_10(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 10);
    }

    @Before("execution(*..*.new(*, *, *, *, *, *, *, *, *, *, *, @javax.annotation.Nonnull (*), ..)) && args(*, *, *, *, *, *, *, *, *, *, *, value, ..)")
    public void notNull_new_11(JoinPoint point, Object value) throws Throwable {
        checkNotNull(point, value, 11);
    }

    @Before("execution(*..*.new(*, *, *, *, *, *, *, *, *, *, *, *, .., @javax.annotation.Nonnull (*), ..))")
    public void notNull_new_moreThan11(JoinPoint point) throws Throwable {
        final ConstructorSignature signature = (ConstructorSignature) point.getSignature();
        final Annotation[][] parameterAnnotations = signature.getConstructor().getParameterAnnotations();
        for (int i=10; i< parameterAnnotations.length; i++){
            for (final Annotation annotation : parameterAnnotations[i]) {
                if (annotation instanceof Nonnull){
                    checkNotNull(point, point.getArgs()[i], i);
                }
            }
        }
    }

    @AfterReturning(pointcut="execution(@javax.annotation.Nonnull * *..*.*(..))", returning="value")
    public void notNull_returnValue(JoinPoint point, Object value) throws Throwable {
        if (value==null){
            final String msg = "method return null";
            final NullPointerException exception = new NullPointerException(msg);
            logger.error(msg, exception);
            throw exception;
        }
    }


    private void checkNotNull(JoinPoint point, Object value, int parameterIndex) {
        if (value == null) {
            final String parameterName = getParameterName(point, parameterIndex);
            final NullPointerException exception = new NullPointerException(parameterName);
            logger.error(parameterName + " is null", exception);
            throw exception;
        }
    }

    private String getParameterName(JoinPoint point, int index) {
        final Signature signature = point.getSignature();
        final CodeSignature code = (CodeSignature) signature;
        final String name = code.getParameterNames()[index];
        return name == null ? String.valueOf(index) : name;
    }
}