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31 
32 package org.jf.dexlib2.util;
33 
34 import com.google.common.base.Predicate;
35 import org.jf.dexlib2.AccessFlags;
36 import org.jf.dexlib2.iface.Method;
37 import org.jf.dexlib2.iface.reference.MethodReference;
38 import org.jf.util.CharSequenceUtils;
39 
40 import javax.annotation.Nonnull;
41 import javax.annotation.Nullable;
42 import java.util.Collection;
43 
44 public final class MethodUtil {
45     private static int directMask = AccessFlags.STATIC.getValue() | AccessFlags.PRIVATE.getValue() |
46             AccessFlags.CONSTRUCTOR.getValue();
47 
48     public static Predicate<Method> METHOD_IS_DIRECT = new Predicate<Method>() {
49         @Override public boolean apply(@Nullable Method input) {
50             return input != null && isDirect(input);
51         }
52     };
53 
54     public static Predicate<Method> METHOD_IS_VIRTUAL = new Predicate<Method>() {
55         @Override public boolean apply(@Nullable Method input) {
56             return input != null && !isDirect(input);
57         }
58     };
59 
isDirect(@onnull Method method)60     public static boolean isDirect(@Nonnull Method method) {
61         return (method.getAccessFlags() & directMask) != 0;
62     }
63 
isStatic(@onnull Method method)64     public static boolean isStatic(@Nonnull Method method) {
65         return AccessFlags.STATIC.isSet(method.getAccessFlags());
66     }
67 
isConstructor(@onnull MethodReference methodReference)68     public static boolean isConstructor(@Nonnull MethodReference methodReference) {
69         return methodReference.getName().equals("<init>");
70     }
71 
isPackagePrivate(@onnull Method method)72     public static boolean isPackagePrivate(@Nonnull Method method) {
73         return (method.getAccessFlags() & (AccessFlags.PRIVATE.getValue() |
74                 AccessFlags.PROTECTED.getValue() |
75                 AccessFlags.PUBLIC.getValue())) == 0;
76     }
77 
getParameterRegisterCount(@onnull Method method)78     public static int getParameterRegisterCount(@Nonnull Method method) {
79         return getParameterRegisterCount(method, MethodUtil.isStatic(method));
80     }
81 
getParameterRegisterCount(@onnull MethodReference methodRef, boolean isStatic)82     public static int getParameterRegisterCount(@Nonnull MethodReference methodRef, boolean isStatic) {
83         return getParameterRegisterCount(methodRef.getParameterTypes(), isStatic);
84     }
85 
getParameterRegisterCount(@onnull Collection<? extends CharSequence> parameterTypes, boolean isStatic)86     public static int getParameterRegisterCount(@Nonnull Collection<? extends CharSequence> parameterTypes,
87                                                 boolean isStatic) {
88         int regCount = 0;
89         for (CharSequence paramType: parameterTypes) {
90             int firstChar = paramType.charAt(0);
91             if (firstChar == 'J' || firstChar == 'D') {
92                 regCount += 2;
93             } else {
94                 regCount++;
95             }
96         }
97         if (!isStatic) {
98             regCount++;
99         }
100         return regCount;
101     }
102 
getShortyType(CharSequence type)103     private static char getShortyType(CharSequence type) {
104         if (type.length() > 1) {
105             return 'L';
106         }
107         return type.charAt(0);
108     }
109 
getShorty(Collection<? extends CharSequence> params, String returnType)110     public static String getShorty(Collection<? extends CharSequence> params, String returnType) {
111         StringBuilder sb = new StringBuilder(params.size() + 1);
112         sb.append(getShortyType(returnType));
113         for (CharSequence typeRef: params) {
114             sb.append(getShortyType(typeRef));
115         }
116         return sb.toString();
117     }
118 
methodSignaturesMatch(@onnull MethodReference a, @Nonnull MethodReference b)119     public static boolean methodSignaturesMatch(@Nonnull MethodReference a, @Nonnull MethodReference b) {
120         return (a.getName().equals(b.getName()) &&
121                 a.getReturnType().equals(b.getReturnType()) &&
122                 CharSequenceUtils.listEquals(a.getParameterTypes(), b.getParameterTypes()));
123     }
124 
MethodUtil()125     private MethodUtil() {}
126 }
127