目标类

public class ConstructTest {        private String notInitStr;        private String initStr;        public ConstructTest(String initStr){        this.initStr = initStr;    }        public String getNotInitStr() {        return notInitStr;    }        public void setNotInitStr(String notInitStr) {        this.notInitStr = notInitStr;    }        public String getInitStr() {        return initStr;    }        public void setInitStr(String initStr) {        this.initStr = initStr;    }}

测试代码：

ConstructTest ct = new ConstructTest("string inited!");System.out.println(ct.getInitStr());System.out.println(ct.getNotInitStr());

测试结果：

null