org.springframework.expression.ExpressionParser Java Examples

@Test
public void SPR9735() {
	Item item = new Item();
	item.setName("parent");

	Item item1 = new Item();
	item1.setName("child1");

	Item item2 = new Item();
	item2.setName("child2");

	item.add(item1);
	item.add(item2);

	ExpressionParser parser = new SpelExpressionParser();
	EvaluationContext context = new StandardEvaluationContext();
	Expression exp = parser.parseExpression("#item[0].name");
	context.setVariable("item", item);

	assertEquals("child1", exp.getValue(context));
}
 

@Test
public void testRootObject() throws Exception {
	GregorianCalendar c = new GregorianCalendar();
	c.set(1856, 7, 9);

	//  The constructor arguments are name, birthday, and nationaltiy.
	Inventor tesla = new Inventor("Nikola Tesla", c.getTime(), "Serbian");

	ExpressionParser parser = new SpelExpressionParser();
	Expression exp = parser.parseExpression("name");

	StandardEvaluationContext context = new StandardEvaluationContext();
	context.setRootObject(tesla);

	String name = (String) exp.getValue(context);
	assertEquals("Nikola Tesla",name);
}
 

@Test
public void testRootObject() throws Exception {
	GregorianCalendar c = new GregorianCalendar();
	c.set(1856, 7, 9);

	//  The constructor arguments are name, birthday, and nationaltiy.
	Inventor tesla = new Inventor("Nikola Tesla", c.getTime(), "Serbian");

	ExpressionParser parser = new SpelExpressionParser();
	Expression exp = parser.parseExpression("name");

	StandardEvaluationContext context = new StandardEvaluationContext();
	context.setRootObject(tesla);

	String name = (String) exp.getValue(context);
	assertEquals("Nikola Tesla",name);
}
 

@Test
public void testGetValuePerformance() throws Exception {
	Assume.group(TestGroup.PERFORMANCE);
	Map<String, String> map = new HashMap<>();
	map.put("key", "value");
	EvaluationContext context = new StandardEvaluationContext(map);

	ExpressionParser spelExpressionParser = new SpelExpressionParser();
	Expression expr = spelExpressionParser.parseExpression("#root['key']");

	StopWatch s = new StopWatch();
	s.start();
	for (int i = 0; i < 10000; i++) {
		expr.getValue(context);
	}
	s.stop();
	assertThat(s.getTotalTimeMillis(), lessThan(200L));
}
 

@Test
@SuppressWarnings("serial")
public void spelExpressionMapWithVariables() {
	ExpressionParser parser = new SpelExpressionParser();
	Expression spelExpression = parser.parseExpression("#aMap['one'] eq 1");
	StandardEvaluationContext ctx = new StandardEvaluationContext();
	ctx.setVariables(new HashMap<String, Object>() {
		{
			put("aMap", new HashMap<String, Integer>() {
				{
					put("one", 1);
					put("two", 2);
					put("three", 3);
				}
			});

		}
	});
	boolean result = spelExpression.getValue(ctx, Boolean.class);
	assertTrue(result);

}
 

@Test
public void SPR10452() {
	SpelParserConfiguration configuration = new SpelParserConfiguration(false, false);
	ExpressionParser parser = new SpelExpressionParser(configuration);

	StandardEvaluationContext context = new StandardEvaluationContext();
	Expression spel = parser.parseExpression("#enumType.values()");

	context.setVariable("enumType", ABC.class);
	Object result = spel.getValue(context);
	assertNotNull(result);
	assertTrue(result.getClass().isArray());
	assertEquals(ABC.A, Array.get(result, 0));
	assertEquals(ABC.B, Array.get(result, 1));
	assertEquals(ABC.C, Array.get(result, 2));

	context.setVariable("enumType", XYZ.class);
	result = spel.getValue(context);
	assertNotNull(result);
	assertTrue(result.getClass().isArray());
	assertEquals(XYZ.X, Array.get(result, 0));
	assertEquals(XYZ.Y, Array.get(result, 1));
	assertEquals(XYZ.Z, Array.get(result, 2));
}
 

@Test
public void SPR9735() {
	Item item = new Item();
	item.setName("parent");

	Item item1 = new Item();
	item1.setName("child1");

	Item item2 = new Item();
	item2.setName("child2");

	item.add(item1);
	item.add(item2);

	ExpressionParser parser = new SpelExpressionParser();
	EvaluationContext context = new StandardEvaluationContext();
	Expression exp = parser.parseExpression("#item[0].name");
	context.setVariable("item", item);

	assertEquals("child1", exp.getValue(context));
}
 

@Test
public void incdecTogether() {
	Spr9751 helper = new Spr9751();
	StandardEvaluationContext ctx = new StandardEvaluationContext(helper);
	ExpressionParser parser = new SpelExpressionParser(new SpelParserConfiguration(true, true));
	Expression e;

	// index1 is 2 at the start - the 'intArray[#root.index1++]' should not be evaluated twice!
	// intArray[2] is 3
	e = parser.parseExpression("intArray[#root.index1++]++");
	e.getValue(ctx, Integer.class);
	assertEquals(3, helper.index1);
	assertEquals(4, helper.intArray[2]);

	// index1 is 3 intArray[3] is 4
	e =  parser.parseExpression("intArray[#root.index1++]--");
	assertEquals(4, e.getValue(ctx, Integer.class).intValue());
	assertEquals(4, helper.index1);
	assertEquals(3, helper.intArray[3]);

	// index1 is 4, intArray[3] is 3
	e =  parser.parseExpression("intArray[--#root.index1]++");
	assertEquals(3, e.getValue(ctx, Integer.class).intValue());
	assertEquals(3, helper.index1);
	assertEquals(4, helper.intArray[3]);
}
 

@Test
public void testGetValuePerformance() throws Exception {
	Assume.group(TestGroup.PERFORMANCE);
	Map<String, String> map = new HashMap<>();
	map.put("key", "value");
	EvaluationContext context = new StandardEvaluationContext(map);

	ExpressionParser spelExpressionParser = new SpelExpressionParser();
	Expression expr = spelExpressionParser.parseExpression("#root['key']");

	StopWatch s = new StopWatch();
	s.start();
	for (int i = 0; i < 10000; i++) {
		expr.getValue(context);
	}
	s.stop();
	assertThat(s.getTotalTimeMillis(), lessThan(200L));
}
 

@Test
@SuppressWarnings("serial")
public void spelExpressionMapWithVariables() {
	ExpressionParser parser = new SpelExpressionParser();
	Expression spelExpression = parser.parseExpression("#aMap['one'] eq 1");
	StandardEvaluationContext ctx = new StandardEvaluationContext();
	ctx.setVariables(new HashMap<String, Object>() {
		{
			put("aMap", new HashMap<String, Integer>() {
				{
					put("one", 1);
					put("two", 2);
					put("three", 3);
				}
			});

		}
	});
	boolean result = spelExpression.getValue(ctx, Boolean.class);
	assertTrue(result);

}
 

@Test
@SuppressWarnings("serial")
public void spelExpressionListIndexAccessWithVariables() {
	ExpressionParser parser = new SpelExpressionParser();
	Expression spelExpression = parser.parseExpression("#aList[0] eq 'one'");
	StandardEvaluationContext ctx = new StandardEvaluationContext();
	ctx.setVariables(new HashMap<String, Object>() {
		{
			put("aList", new ArrayList<String>() {
				{
					add("one");
					add("two");
					add("three");
				}
			});

		}
	});
	boolean result = spelExpression.getValue(ctx, Boolean.class);
	assertTrue(result);
}
 

@Test
@SuppressWarnings("serial")
public void spelExpressionListIndexAccessWithVariables() {
	ExpressionParser parser = new SpelExpressionParser();
	Expression spelExpression = parser.parseExpression("#aList[0] eq 'one'");
	StandardEvaluationContext ctx = new StandardEvaluationContext();
	ctx.setVariables(new HashMap<String, Object>() {
		{
			put("aList", new ArrayList<String>() {
				{
					add("one");
					add("two");
					add("three");
				}
			});

		}
	});
	boolean result = spelExpression.getValue(ctx, Boolean.class);
	assertTrue(result);
}
 

/**
 * Test the ability to subclass the ReflectiveMethodResolver and change how it
 * determines the set of methods for a type.
 */
@Test
public void customStaticFunctions_SPR9038() {
	ExpressionParser parser = new SpelExpressionParser();
	StandardEvaluationContext context = new StandardEvaluationContext();
	List<MethodResolver> methodResolvers = new ArrayList<>();
	methodResolvers.add(new ReflectiveMethodResolver() {
		@Override
		protected Method[] getMethods(Class<?> type) {
			try {
				return new Method[] {Integer.class.getDeclaredMethod("parseInt", String.class, Integer.TYPE)};
			}
			catch (NoSuchMethodException ex) {
				return new Method[0];
			}
		}
	});

	context.setMethodResolvers(methodResolvers);
	Expression expression = parser.parseExpression("parseInt('-FF', 16)");

	Integer result = expression.getValue(context, "", Integer.class);
	assertEquals(-255, result.intValue());
}
 

/**
 * 获取缓存的key
 * key 定义在注解上，支持SPEL表达式
 */
private String parseKey(String key, Method method, Object[] args) {
    //获取被拦截方法参数名列表(使用Spring支持类库)
    LocalVariableTableParameterNameDiscoverer u =
            new LocalVariableTableParameterNameDiscoverer();
    String[] paraNameArr = u.getParameterNames(method);

    //使用SPEL进行key的解析
    ExpressionParser parser = new SpelExpressionParser();
    //SPEL上下文
    StandardEvaluationContext context = new StandardEvaluationContext();
    //把方法参数放入SPEL上下文中
    for (int i = 0; i < paraNameArr.length; i++) {
        context.setVariable(paraNameArr[i], args[i]);
    }
    return parser.parseExpression(key).getValue(context, String.class);
}
 

/**
 * 支持 #p0 参数索引的表达式解析
 * @param rootObject 根对象,method 所在的对象
 * @param spel 表达式
 * @param method ，目标方法
 * @param args 方法入参
 * @return 解析后的字符串
 */
public static String parse(Object rootObject,String spel, Method method, Object[] args) {
    if (StrUtil.isBlank(spel)) {
        return StrUtil.EMPTY;
    }
    //获取被拦截方法参数名列表(使用Spring支持类库)
    LocalVariableTableParameterNameDiscoverer u =
            new LocalVariableTableParameterNameDiscoverer();
    String[] paraNameArr = u.getParameterNames(method);
    if (ArrayUtil.isEmpty(paraNameArr)) {
        return spel;
    }
    //使用SPEL进行key的解析
    ExpressionParser parser = new SpelExpressionParser();
    //SPEL上下文
    StandardEvaluationContext context = new MethodBasedEvaluationContext(rootObject,method,args,u);
    //把方法参数放入SPEL上下文中
    for (int i = 0; i < paraNameArr.length; i++) {
        context.setVariable(paraNameArr[i], args[i]);
    }
    return parser.parseExpression(spel).getValue(context, String.class);
}
 

@Test
public void SPR9486_floatPowerFloat() {
	Number expectedResult = Math.pow(10.21f, -10.2f);
	ExpressionParser parser = new SpelExpressionParser();
	StandardEvaluationContext context = new StandardEvaluationContext();
	Expression expression = parser.parseExpression("10.21f ^ -10.2f");
	Number result = expression.getValue(context, null, Number.class);
	assertEquals(expectedResult, result);
}
 

@Test
public void SPR9486_floatEqDouble() {
	Boolean expectedResult = 10.215f == 10.2109;
	ExpressionParser parser = new SpelExpressionParser();
	StandardEvaluationContext context = new StandardEvaluationContext();
	Expression expression = parser.parseExpression("10.215f == 10.2109");
	Boolean result = expression.getValue(context, null, Boolean.class);
	assertEquals(expectedResult, result);
}
 

@Test
public void SPR9486_floatEqFloat() {
	Boolean expectedResult = 10.215f == 10.2109f;
	ExpressionParser parser = new SpelExpressionParser();
	StandardEvaluationContext context = new StandardEvaluationContext();
	Expression expression = parser.parseExpression("10.215f == 10.2109f");
	Boolean result = expression.getValue(context, null, Boolean.class);
	assertEquals(expectedResult, result);
}
 

@Test
public void SPR9486_floatEqDoubleUnaryMinus() {
	Boolean expectedResult = -10.21f == -10.2;
	ExpressionParser parser = new SpelExpressionParser();
	StandardEvaluationContext context = new StandardEvaluationContext();
	Expression expression = parser.parseExpression("-10.21f == -10.2");
	Boolean result = expression.getValue(context, null, Boolean.class);
	assertEquals(expectedResult, result);
}
 

@Test
public void SPR10091_primitiveTestValueType() {
	ExpressionParser parser = new SpelExpressionParser();
	StandardEvaluationContext evaluationContext = new StandardEvaluationContext(new BooleanHolder());
	Class<?> valueType = parser.parseExpression("primitiveProperty").getValueType(evaluationContext);
	assertNotNull(valueType);
}
 

@Test
public void SPR9486_floatGreaterThanEqualDouble() {
	Boolean expectedResult = -10.21f >= -10.2;
	ExpressionParser parser = new SpelExpressionParser();
	StandardEvaluationContext context = new StandardEvaluationContext();
	Expression expression = parser.parseExpression("-10.21f >= -10.2");
	Boolean result = expression.getValue(context, null, Boolean.class);
	assertEquals(expectedResult, result);
}
 

private void expectFail(ExpressionParser parser, EvaluationContext eContext, String expressionString, SpelMessage messageCode) {
	try {
		Expression e = parser.parseExpression(expressionString);
		SpelUtilities.printAbstractSyntaxTree(System.out, e);
		e.getValue(eContext);
		fail();
	}
	catch (SpelEvaluationException see) {
		assertEquals(messageCode, see.getMessageCode());
	}
}
 

@Test
public void SPR13055_maps() {
	EvaluationContext context = new StandardEvaluationContext();
	ExpressionParser parser = new SpelExpressionParser();

	Expression ex = parser.parseExpression("{'a':'y','b':'n'}.![value=='y'?key:null]");
	assertEquals("[a, null]", ex.getValue(context).toString());

	ex = parser.parseExpression("{2:4,3:6}.![T(java.lang.Math).abs(#this.key) + 5]");
	assertEquals("[7, 8]", ex.getValue(context).toString());

	ex = parser.parseExpression("{2:4,3:6}.![T(java.lang.Math).abs(#this.value) + 5]");
	assertEquals("[9, 11]", ex.getValue(context).toString());
}
 

@Test
public void SPR9486_multiplyFloatWithDouble() {
	Number expectedNumber = 10.21f * 10.2;
	ExpressionParser parser = new SpelExpressionParser();
	StandardEvaluationContext context = new StandardEvaluationContext();
	Expression expression = parser.parseExpression("10.21f * 10.2");
	Number result = expression.getValue(context, null, Number.class);
	assertEquals(expectedNumber, result);
}
 

@Test
public void SPR9486_subtractFloatWithFloat() {
	Number expectedNumber = 10.21f - 10.2f;
	ExpressionParser parser = new SpelExpressionParser();
	StandardEvaluationContext context = new StandardEvaluationContext();
	Expression expression = parser.parseExpression("10.21f - 10.2f");
	Number result = expression.getValue(context, null, Number.class);
	assertEquals(expectedNumber, result);
}
 

@Test
public void increment01root() {
	Integer i = 42;
	StandardEvaluationContext ctx = new StandardEvaluationContext(i);
	ExpressionParser parser = new SpelExpressionParser(new SpelParserConfiguration(true, true));
	Expression e =  parser.parseExpression("#this++");
	assertEquals(42,i.intValue());
	try {
		e.getValue(ctx, Integer.class);
		fail();
	}
	catch (SpelEvaluationException see) {
		assertEquals(SpelMessage.NOT_ASSIGNABLE, see.getMessageCode());
	}
}
 

@Test
public void SPR9486_floatLessThanFloat() {
	Boolean expectedNumber = -10.21f < -10.2f;
	ExpressionParser parser = new SpelExpressionParser();
	StandardEvaluationContext context = new StandardEvaluationContext();
	Expression expression = parser.parseExpression("-10.21f < -10.2f");
	Boolean result = expression.getValue(context, null, Boolean.class);
	assertEquals(expectedNumber, result);
}
 

@Test
public void SPR9486_floatFunctionResolver() {
	Number expectedResult = Math.abs(-10.2f);
	ExpressionParser parser = new SpelExpressionParser();
	SPR9486_FunctionsClass testObject = new SPR9486_FunctionsClass();

	StandardEvaluationContext context = new StandardEvaluationContext();
	Expression expression = parser.parseExpression("abs(-10.2f)");
	Number result = expression.getValue(context, testObject, Number.class);
	assertEquals(expectedResult, result);
}
 

@Test
public void SPR10091_simpleTestValue() {
	ExpressionParser parser = new SpelExpressionParser();
	StandardEvaluationContext evaluationContext = new StandardEvaluationContext(new BooleanHolder());
	Object value = parser.parseExpression("simpleProperty").getValue(evaluationContext);
	assertNotNull(value);
}
 

/**
 * Verifies behavior requested in SPR-9613.
 */
@Test
public void caseInsensitiveNullLiterals() {
	ExpressionParser parser = new SpelExpressionParser();

	Expression e = parser.parseExpression("null");
	assertNull(e.getValue());

	e = parser.parseExpression("NULL");
	assertNull(e.getValue());

	e = parser.parseExpression("NuLl");
	assertNull(e.getValue());
}