import com.sun.tools.internal.xjc.outline.FieldAccessor; //导入依赖的package包/类
private void generate( ClassOutlineImpl outline, CPropertyInfo prop ) {
    // add isSetXXX and unsetXXX.
    MethodWriter writer = outline.createMethodWriter();

    JCodeModel codeModel = outline.parent().getCodeModel();

    FieldAccessor acc = core.create(JExpr._this());

    if( generateIsSetMethod ) {
        // [RESULT] boolean isSetXXX()
        JExpression hasSetValue = acc.hasSetValue();
        if( hasSetValue==null ) {
            // this field renderer doesn't support the isSet/unset methods generation.
            // issue an error
            throw new UnsupportedOperationException();
        }
        writer.declareMethod(codeModel.BOOLEAN,"isSet"+this.prop.getName(true))
            .body()._return( hasSetValue );
    }

    if( generateUnSetMethod ) {
        // [RESULT] void unsetXXX()
        acc.unsetValues(
            writer.declareMethod(codeModel.VOID,"unset"+this.prop.getName(true)).body() );
    }
}
 

import com.sun.tools.internal.xjc.outline.FieldAccessor; //导入依赖的package包/类
public FieldAccessor create(JExpression targetObject) {
    return new Accessor(targetObject) {

        public void unsetValues( JBlock body ) {
            // you can't unset a value
        }

        public JExpression hasSetValue() {
            return JExpr.TRUE;
        }
    };
}
 

import com.sun.tools.internal.xjc.outline.FieldAccessor; //导入依赖的package包/类
public FieldAccessor create(JExpression targetObject) {
    return new Accessor(targetObject);
}
 

import com.sun.tools.internal.xjc.outline.FieldAccessor; //导入依赖的package包/类
public FieldAccessor create(JExpression target) {
    return new Accessor(target);
}
 

import com.sun.tools.internal.xjc.outline.FieldAccessor; //导入依赖的package包/类
public FieldAccessor create(JExpression targetObject) {
    return new FieldAccessorImpl(targetObject);
}