Here you can find the source of assertTrue(boolean evalResult, Object... messages)
public static void assertTrue(boolean evalResult, Object... messages)
//package com.java2s; /*/*from www . ja v a 2 s . c o m*/ * Copyright 2004-2010 the Seasar Foundation and the Others. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, * either express or implied. See the License for the specific language * governing permissions and limitations under the License. */ public class Main { public static void assertTrue(boolean evalResult, Object... messages) { if (!evalResult) { StringBuilder buf = new StringBuilder(); for (Object message : messages) { buf.append(message.toString()); buf.append(", "); } if (buf.length() > 0) { buf.setLength(buf.length() - 2); } throw new AssertionError("Unfulfilled. " + buf.toString()); } } }