Java SpelNode类代码示例

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
@Override
public TypedValue getValueInternal(ExpressionState expressionState) throws EvaluationException {
	if (this.constant != null) {
		return this.constant;
	}
	else {
		Map<Object, Object> returnValue = new LinkedHashMap<Object, Object>();
		int childcount = getChildCount();
		for (int c = 0; c < childcount; c++) {
			// TODO allow for key being PropertyOrFieldReference like Indexer on maps
			SpelNode keyChild = getChild(c++);
			Object key = null;
			if (keyChild instanceof PropertyOrFieldReference) {
				PropertyOrFieldReference reference = (PropertyOrFieldReference) keyChild;
				key = reference.getName();
			}
			else {
				key = keyChild.getValue(expressionState);
			}
			Object value = getChild(c).getValue(expressionState);
			returnValue.put(key,  value);
		}
		return new TypedValue(returnValue);
	}
}
 

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
private void handle(SpelNode node, Class<?> expressionRoot) throws ExpressionValidationException{
    if (node instanceof MethodReference) {
        verify((MethodReference) node, expressionRoot);
    } else if (node instanceof Operator) {
        Operator operator = (Operator) node;
        handle(operator.getLeftOperand(), expressionRoot);
        handle(operator.getRightOperand(), expressionRoot);
    } else if (node != null) {
        for(int i=0; i<node.getChildCount(); i++) {
            SpelNode child = node.getChild(i);
            if (child instanceof VariableReference ||
                    child instanceof TypeReference ||
                    child instanceof BeanReference) {
                // stop inspecting if it's a variable or type reference.
                // We can handle this later if we get smart about resolving these
                break;
            }
            handle(child, expressionRoot);
        }
    }
}
 

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
/**
 * Looks for permissions in given node and all its children
 *
 * @param node node that will be searched for permissions
 * @return list of permissions
 */
private List<String> findPermissions(SpelNode node) {
    List<String> list = new ArrayList<>(node.getChildCount());

    if (startsWithIgnoreCase(node.toStringAST(), "hasRole") || startsWithIgnoreCase(node.toStringAST(), "hasAnyRole")) {
        for (int i = 0; i < node.getChildCount(); ++i) {
            list.add(remove(node.getChild(i).toStringAST(), '\''));
        }
    } else {
        for (int i = 0; i < node.getChildCount(); ++i) {
            list.addAll(findPermissions(node.getChild(i)));
        }
    }

    LOGGER.debug("Found permissions: {}", list);

    return list;
}
 

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
private void populateReferenceTypeArray(ExpressionState state, Object newArray, TypeConverter typeConverter,
		InlineList initializer, Class<?> componentType) {
	TypeDescriptor toTypeDescriptor = TypeDescriptor.valueOf(componentType);
	Object[] newObjectArray = (Object[]) newArray;
	for (int i = 0; i < newObjectArray.length; i++) {
		SpelNode elementNode = initializer.getChild(i);
		Object arrayEntry = elementNode.getValue(state);
		newObjectArray[i] = typeConverter.convertValue(arrayEntry, TypeDescriptor.forObject(arrayEntry), toTypeDescriptor);
	}
}
 

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
private void populateReferenceTypeArray(ExpressionState state, Object newArray, TypeConverter typeConverter,
		InlineList initializer, Class<?> componentType) {

	TypeDescriptor toTypeDescriptor = TypeDescriptor.valueOf(componentType);
	Object[] newObjectArray = (Object[]) newArray;
	for (int i = 0; i < newObjectArray.length; i++) {
		SpelNode elementNode = initializer.getChild(i);
		Object arrayEntry = elementNode.getValue(state);
		newObjectArray[i] = typeConverter.convertValue(arrayEntry,
				TypeDescriptor.forObject(arrayEntry), toTypeDescriptor);
	}
}
 

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
@Test
public void positionalInformation() throws EvaluationException, ParseException {
	SpelExpression expr = new SpelExpressionParser().parseRaw("true and true or false");
	SpelNode rootAst = expr.getAST();
	OpOr operatorOr = (OpOr) rootAst;
	OpAnd operatorAnd = (OpAnd) operatorOr.getLeftOperand();
	SpelNode rightOrOperand = operatorOr.getRightOperand();

	// check position for final 'false'
	assertEquals(17, rightOrOperand.getStartPosition());
	assertEquals(22, rightOrOperand.getEndPosition());

	// check position for first 'true'
	assertEquals(0, operatorAnd.getLeftOperand().getStartPosition());
	assertEquals(4, operatorAnd.getLeftOperand().getEndPosition());

	// check position for second 'true'
	assertEquals(9, operatorAnd.getRightOperand().getStartPosition());
	assertEquals(13, operatorAnd.getRightOperand().getEndPosition());

	// check position for OperatorAnd
	assertEquals(5, operatorAnd.getStartPosition());
	assertEquals(8, operatorAnd.getEndPosition());

	// check position for OperatorOr
	assertEquals(14, operatorOr.getStartPosition());
	assertEquals(16, operatorOr.getEndPosition());
}
 

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
public void validate(String expression, Class<?> expressionRoot) throws ExpressionValidationException, ParseException {
    SpelExpression exp = (SpelExpression) parser.parseExpression(expression);
    if (expressionRoot != null) {
        SpelNode node = exp.getAST();
        handle(node, expressionRoot);
    }
}
 

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
private static void printAST(PrintStream out, SpelNode t, String indent) {
	if (t != null) {
		StringBuilder sb = new StringBuilder();
		sb.append(indent).append(t.getClass().getSimpleName());
		sb.append("  value:").append(t.toStringAST());
		sb.append(t.getChildCount() < 2 ? "" : "  #children:" + t.getChildCount());
		out.println(sb.toString());
		for (int i = 0; i < t.getChildCount(); i++) {
			printAST(out, t.getChild(i), indent + "  ");
		}
	}
}
 

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
@Override
public SpelNode getChild(int index) {
	return this.children[index];
}
 

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
/**
 * @return return the Abstract Syntax Tree for the expression
 */
public SpelNode getAST() {
	return this.ast;
}
 

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
/**
 * If all the components of the list are constants, or lists/maps that themselves
 * contain constants, then a constant list can be built to represent this node.
 * This will speed up later getValue calls and reduce the amount of garbage created.
 */
private void checkIfConstant() {
	boolean isConstant = true;
	for (int c = 0, max = getChildCount(); c < max; c++) {
		SpelNode child = getChild(c);
		if (!(child instanceof Literal)) {
			if (child instanceof InlineList) {
				InlineList inlineList = (InlineList) child;
				if (!inlineList.isConstant()) {
					isConstant = false;
					break;
				}
			}
			else if (child instanceof InlineMap) {
				InlineMap inlineMap = (InlineMap) child;
				if (!inlineMap.isConstant()) {
					isConstant = false;
					break;
				}
			}
			else if (!((c%2)==0 && (child instanceof PropertyOrFieldReference))) {					
				isConstant = false;
				break;
			}
		}
	}
	if (isConstant) {
		Map<Object,Object> constantMap = new LinkedHashMap<Object,Object>();			
		int childCount = getChildCount();
		for (int c = 0; c < childCount; c++) {
			SpelNode keyChild = getChild(c++);
			SpelNode valueChild = getChild(c);
			Object key = null;
			Object value = null;
			if (keyChild instanceof Literal) {
				key = ((Literal) keyChild).getLiteralValue().getValue();
			}
			else if (keyChild instanceof PropertyOrFieldReference) {
				key = ((PropertyOrFieldReference) keyChild).getName();
			}
			else {
				return;
			}
			if (valueChild instanceof Literal) {
				value = ((Literal) valueChild).getLiteralValue().getValue();
			}
			else if (valueChild instanceof InlineList) {
				value = ((InlineList) valueChild).getConstantValue();
			}
			else if (valueChild instanceof InlineMap) {
				value = ((InlineMap) valueChild).getConstantValue();
			}
			constantMap.put(key, value);
		}
		this.constant = new TypedValue(Collections.unmodifiableMap(constantMap));
	}
}
 

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
/**
 * Return the Abstract Syntax Tree for the expression.
 */
public SpelNode getAST() {
	return this.ast;
}
 

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
public SpelNode getChild(int index) {
	return children[index];
}
 

import org.springframework.expression.spel.SpelNode; //导入依赖的package包/类
/**
 * @return return the Abstract Syntax Tree for the expression
 */
public SpelNode getAST() {
	return ast;
}